Designs

13 pages, 3203 KB

Open AccessEditor’s ChoiceArticle

Effect of Curvature Shape on the Impact Strength of Additively Manufactured Acrylonitrile Butadiene Styrene Parts Produced via Fused Deposition Modeling

by Muhammad Fahad, Waseem Raja, Muhammad Naveed Iqbal and Abdul Waheed Awan

Designs 2024, 8(6), 132; https://doi.org/10.3390/designs8060132 - 8 Dec 2024

Cited by 1 | Viewed by 1257

Abstract

Additive manufacturing (AM) has greatly revolutionized manufacturing due to its ability to manufacture complex shapes without the need for additional tooling. Most AM applications are based on geometries comprising curved shapes subjected to impact loads. The main focus of this study was on [...] Read more.

Additive manufacturing (AM) has greatly revolutionized manufacturing due to its ability to manufacture complex shapes without the need for additional tooling. Most AM applications are based on geometries comprising curved shapes subjected to impact loads. The main focus of this study was on investigating the influence of infill density and the radius of curvature on the impact strength of parts manufactured via an FDM process. Standard geometrical specimens with varying part infill densities and radii of curvature were produced and subjected to Charpy impact tests to evaluate their impact strength. The results suggest that the impact strength increases with the increased density caused by higher amounts of material as well as by the changing cross-sectional areas of the beads. Also, the radius of curvature of the parts shows a clear inverse relationship with the impact energy absorbed by the specimens (i.e., increasing the radius decreased the impact energy of the parts) produced via an FDM process, which can be explained using the beam theory of structural mechanics. The maximum value of impact strength obtained was 287 KJ/m², and this was achieved at the highest infill density (i.e., solid) and for the smallest radius of curvature. Full article

(This article belongs to the Special Issue Post-manufacturing Testing and Characterization of Materials)

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18 pages, 17110 KB

Open AccessEditor’s ChoiceArticle

Contribution of Artificial Intelligence (AI) to Code-Based 3D Modeling Tasks

by Marianna Zichar and Ildikó Papp

Designs 2024, 8(5), 104; https://doi.org/10.3390/designs8050104 - 18 Oct 2024

Cited by 2 | Viewed by 1817

Abstract

The rapid advancement of technology and innovation is also impacting education across different levels. The rise of Artificial Intelligence (AI) is beginning to transform education in various areas, from course materials to assessment systems. This requires educators to reconsider how they evaluate students’ [...] Read more.

The rapid advancement of technology and innovation is also impacting education across different levels. The rise of Artificial Intelligence (AI) is beginning to transform education in various areas, from course materials to assessment systems. This requires educators to reconsider how they evaluate students’ knowledge. It is crucial to understand if and to what extent assignments can be completed using AI tools. This study explores two hypotheses about the risks of using code-based 3D modeling software in education and the potential for students to delegate their work to AI when completing assignments. We selected two tasks that students were able to successfully complete independently and provided the same amount of information (both textual and image) to AI in order to generate the necessary code. We tested the widely used ChatGPT and Gemini AI bots to assess their current performance in generating code based on text prompts or image-based information for the two models. Our findings indicate that students are not yet able to entirely delegate their work to these AI tools. Full article

(This article belongs to the Special Issue Design Process for Additive Manufacturing)

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15 pages, 7363 KB

Open AccessEditor’s ChoiceArticle

Integrating Pneumatic and Thermal Control in 3D Bioprinting for Improved Bio-Ink Handling

by Perrin Woods, Carter Smith, Scott Clark and Ahasan Habib

Designs 2024, 8(4), 83; https://doi.org/10.3390/designs8040083 - 22 Aug 2024

Cited by 6 | Viewed by 2187

Abstract

The rapid advancement of 3D bioprinting has created a need for cost-effective and versatile 3D printers capable of handling bio-inks at various scales. This study introduces a novel framework for a specialized nozzle-holding device designed for an extrusion-based 3D bioprinter, specifically tailored to [...] Read more.

The rapid advancement of 3D bioprinting has created a need for cost-effective and versatile 3D printers capable of handling bio-inks at various scales. This study introduces a novel framework for a specialized nozzle-holding device designed for an extrusion-based 3D bioprinter, specifically tailored to address the rigorous requirements of tissue engineering applications. The proposed system combines a pneumatically actuated plunger mechanism with an adaptive nozzle system, ensuring the safe inhibition and precise dispensing of bio-inks. Rigorous thermal management strategies are employed to maintain consistently low temperatures, thereby preserving bio-ink integrity without changing chemical stability. A key component of this design is a precision-milled aluminum block, which optimizes thermal characteristics while providing a protective barrier. Additionally, a 3D-printed extruder head bracket, fabricated using a high-precision resin printer, effectively mitigates potential thermal inconsistencies. The integration of these meticulously engineered components results in a modified extrusion-based 3D bioprinter with the potential to significantly advance tissue engineering methodologies. This study not only contributes to the advancement of bioprinting technology but also underscores the crucial role of innovative engineering in addressing tissue engineering challenges. The proposed bioprinter design lays a solid foundation for future research, aiming to develop more accurate, efficient, and reliable bioprinting solutions. Full article

(This article belongs to the Special Issue Design Process for Additive Manufacturing)

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26 pages, 4301 KB

Open AccessEditor’s ChoiceArticle

Optimized Floating Offshore Wind Turbine Substructure Design Trends for 10–30 MW Turbines in Low-, Medium-, and High-Severity Wave Environments

by Joseph Habib Dagher, Andrew J. Goupee and Anthony M. Viselli

Designs 2024, 8(4), 72; https://doi.org/10.3390/designs8040072 - 18 Jul 2024

Cited by 3 | Viewed by 3951

Abstract

Floating offshore wind is a promising renewable energy source, as 60% of the wind resources globally are found at depths requiring floating technologies, it minimizes construction at sea, and provides opportunities for industrialization given a lower site dependency. While floating offshore wind has [...] Read more.

Floating offshore wind is a promising renewable energy source, as 60% of the wind resources globally are found at depths requiring floating technologies, it minimizes construction at sea, and provides opportunities for industrialization given a lower site dependency. While floating offshore wind has numerous advantages, a current obstacle is its cost in comparison to more established energy sources. One cost-reduction approach for floating wind is increasing turbine capacities, which minimizes the amount of foundations, moorings, cables, and O&M equipment. This work presents trends in mass-optimized VolturnUS hull designs as turbine capacity increases for various wave environments. To do this, a novel rapid hull optimization framework is presented that employs frequency domain modeling, estimations of statistical extreme responses, industry constructability requirements, and genetic algorithm optimization to generate preliminary mass-optimal VolturnUS hull designs for a given turbine design and set of site conditions. Using this framework, mass-optimized VolturnUS hull designs were generated for 10–30 MW turbines for wave environments of varying severities. These design studies show that scaling up turbine capacities increases the mass efficiency of substructure designs, with decreasing returns, throughout the examined turbine capacity range. Additionally, increased wave environment severity is shown to increase the required mass of a given substructure design. Full article

(This article belongs to the Special Issue Design and Analysis of Offshore Wind Turbines)

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20 pages, 11203 KB

Open AccessEditor’s ChoiceArticle

Dimensional Accuracy in 4D-Printed PLA Objects with Holes: Experimental and Numerical Investigations

by Alexandru-Antonio Ene, Tudor George Alexandru and Diana Popescu

Designs 2024, 8(3), 56; https://doi.org/10.3390/designs8030056 - 6 Jun 2024

Cited by 2 | Viewed by 1820

Abstract

This study investigates the impact of material and process parameters—specifically, filament color, infill density, and pattern—on the dimensional accuracy of 4D-printed polylactic acid (PLA) objects featuring holes of varying diameters (6, 8, and 10 mm) that undergo a heat-induced recovery process. The objective [...] Read more.

This study investigates the impact of material and process parameters—specifically, filament color, infill density, and pattern—on the dimensional accuracy of 4D-printed polylactic acid (PLA) objects featuring holes of varying diameters (6, 8, and 10 mm) that undergo a heat-induced recovery process. The objective was to understand how these factors affect shape retention and the dimensional accuracy of holes through a comparative analysis of the diameters before and after recovery. Increased variability in the hole diameters was noted after recovery, regardless of the values of the independent variables. The objects did not fully return to their original planar shape, and the holes did not completely return to their circular form, resulting in smaller diameters for each sample. No significant differences in the hole diameters could be determined. Additionally, there was no consistent trend in identifying the most influential parameter affecting the accuracy of the recovered holes. However, it was observed that higher infill densities improved shape retention. A quasi-static finite elements analysis model was developed to capture the mechanical behavior of the 4D-printed parts. This model incorporated temperature-dependent material characteristics to predict the strain occurring near the holes. Nodal displacements were defined according to the deformed shape. A correlation was established between the observed strains and the post-recovery dimensional accuracy of the specimens. The importance of this work was demonstrated through a case study involving a two-sieve filtering device for small objects. Full article

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20 pages, 8159 KB

Open AccessEditor’s ChoiceArticle

Towards a Sustainable Laser Powder Bed Fusion Process via the Characterisation of Additively Manufactured Nitinol Parts

by Muhannad Ahmed Obeidi, Paul Healy, Hasan Alobaidi, Declan Bourke and Dermot Brabazon

Designs 2024, 8(3), 45; https://doi.org/10.3390/designs8030045 - 15 May 2024

Cited by 4 | Viewed by 2862

Abstract

Is additive manufacturing (AM) a sustainable process? Can the process be optimised to produce sustainable AM parts and production techniques? Additive manufacturing offers the production of parts made of different types of materials in addition to the complex geometry that is difficult or [...] Read more.

Is additive manufacturing (AM) a sustainable process? Can the process be optimised to produce sustainable AM parts and production techniques? Additive manufacturing offers the production of parts made of different types of materials in addition to the complex geometry that is difficult or impossible to produce by using the traditional subtractive methods. This study is focused on the optimisation of laser powder bed fusion (L-PBF), one of the most common technologies used in additive manufacturing and 3D printing. This research was carried out by modulating the build layer thickness of the deposited metal powder and the input volumetric energy density. The aim of the proposed strategy is to save the build time by maximizing the applied layer thickness of nitinol powder while retrieving the different AM part properties. The saving in the process time has a direct effect on the total cost of the produced part as a result of several components like electric energy, inert gas consumption, and labour. Nickel-rich nitinol (52.39 Ni at.%) was selected for investigation in this study due to its extremely high superplastic and shape memory properties in addition to the wide application in various industries like aerospace, biomedical, and automotive. The results obtained show that significant energy and material consumption can be found by producing near full dens AM parts with limited or no alteration in chemical and mechanical properties. Full article

(This article belongs to the Section Mechanical Engineering Design)

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19 pages, 13288 KB

Open AccessEditor’s ChoiceArticle

Monitoring the Center of Gravity of a Vehicle Seat to Detect the Occupant Position

by Alberto Vergnano, Claudio Giorgianni and Francesco Leali

Designs 2024, 8(3), 44; https://doi.org/10.3390/designs8030044 - 15 May 2024

Cited by 4 | Viewed by 2618

Abstract

Deploying an airbag when a vehicle occupant is too close to it can cause injury. An adaptive Airbag Control Unit (ACU) would improve the effectiveness of the safety system, provided it is aware of the actual position of the occupants once the crash [...] Read more.

Deploying an airbag when a vehicle occupant is too close to it can cause injury. An adaptive Airbag Control Unit (ACU) would improve the effectiveness of the safety system, provided it is aware of the actual position of the occupants once the crash is going to occur. Occupants can be monitored with vision-based and radar-based sensing in the vehicle, but the research question is whether other reliable devices exist. In this research, a real seat is equipped with four sensors in the supports from the floor, as well as an Inertial Measurement Unit (IMU) and a microcontroller. The device is capable of identifying correct position or different Out of Position (OP) conditions and inform an adaptive ACU. The paper presents the seat layout in detail and its testing in extensive driving experiments with multiple participants. Depending on the position of the driver, the identification is correct 45–100% of the time. Monitoring the occupant position by a sensorized seat is feasible and can improve the reliability of the onboard safety system when integrated with other occupant monitoring devices. Full article

(This article belongs to the Section Vehicle Engineering Design)

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21 pages, 10990 KB

Open AccessEditor’s ChoiceArticle

Electromagnetic Interaction Model between an Electric Motor and a Magnetorheological Brake

by Sidorela Caushaj, Giovanni Imberti, Henrique de Carvalho Pinheiro and Massimiliana Carello

Designs 2024, 8(2), 25; https://doi.org/10.3390/designs8020025 - 14 Mar 2024

Cited by 3 | Viewed by 2465

Abstract

This article focuses on modelling and validating a groundbreaking magnetorheological braking system. Addressing shortcomings in traditional automotive friction brake systems, including response delays, wear, and added mass from auxiliary components, the study employs a novel brake design combining mechanical and electrical elements for [...] Read more.

This article focuses on modelling and validating a groundbreaking magnetorheological braking system. Addressing shortcomings in traditional automotive friction brake systems, including response delays, wear, and added mass from auxiliary components, the study employs a novel brake design combining mechanical and electrical elements for enhanced efficiency. Utilizing magnetorheological (MR) technology within a motor–brake system, the investigation explores the influence of external magnetic flux from the nearby motor on MR fluid movement, particularly under high-flux conditions. The evaluation of a high-magnetic-field mitigator is guided by simulated findings with the objective of resolving potential issues. An alternative method of resolving an interaction between an electric motor and a magnetorheological brake is presented. In addition, to test four configurations, multiple absorber materials are reviewed. Full article

(This article belongs to the Special Issue Design and Manufacture of Electric Vehicles)

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73 pages, 35413 KB

Open AccessEditor’s ChoiceReview

A Review of Novel and Non-Conventional Propulsion Integrations for Next-Generation Aircraft

by Karim Abu Salem, Giuseppe Palaia, Pedro D. Bravo-Mosquera and Alessandro A. Quarta

Designs 2024, 8(2), 20; https://doi.org/10.3390/designs8020020 - 20 Feb 2024

Cited by 13 | Viewed by 7404

Abstract

The aim of this review paper is to collect and discuss the most relevant and updated contributions in the literature regarding studies on new or non-conventional technologies for propulsion–airframe integration. Specifically, the focus is given to both evolutionary technologies, such as ultra-high bypass [...] Read more.

The aim of this review paper is to collect and discuss the most relevant and updated contributions in the literature regarding studies on new or non-conventional technologies for propulsion–airframe integration. Specifically, the focus is given to both evolutionary technologies, such as ultra-high bypass ratio turbofan engines, and breakthrough propulsive concepts, represented in this frame by boundary layer ingestion engines and distributed propulsion architectures. The discussion focuses mainly on the integration effects of these propulsion technologies, with the aim of defining performance interactions with the overall aircraft, in terms of aerodynamic, propulsive, operating and mission performance. Hence, this work aims to analyse these technologies from a general perspective, related to the effects they have on overall aircraft design and performance, primarily considering the fuel consumption as a main metric. Potential advantages but also possible drawbacks or detected showstoppers are proposed and discussed with the aim of providing as broad a framework as possible for the aircraft design development roadmap for these emerging propulsive technologies. Full article

(This article belongs to the Special Issue Advances in Aircraft Propulsion System Modelling, Design and Simulation)

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21 pages, 847 KB

Open AccessEditor’s ChoiceArticle

Incorporating a Load-Shifting Algorithm for Optimal Energy Storage Capacity Design in Smart Homes

by Ruengwit Khwanrit, Yuto Lim, Saher Javaid, Chalie Charoenlarpnopparut and Yasuo Tan

Designs 2024, 8(1), 11; https://doi.org/10.3390/designs8010011 - 22 Jan 2024

Cited by 5 | Viewed by 2661

Abstract

In today’s power system landscape, renewable energy (RE) resources play a pivotal role, particularly within the residential sector. Despite the significance of these resources, the intermittent nature of RE resources, influenced by variable weather conditions, poses challenges to their reliability as energy resources. [...] Read more.

In today’s power system landscape, renewable energy (RE) resources play a pivotal role, particularly within the residential sector. Despite the significance of these resources, the intermittent nature of RE resources, influenced by variable weather conditions, poses challenges to their reliability as energy resources. Addressing this challenge, the integration of an energy storage system (ESS) emerges as a viable solution, enabling the storage of surplus energy during peak-generation periods and subsequent release during shortages. One of the great challenges of ESSs is how to design ESSs efficiently. This paper focuses on a distributed power-flow system within a smart home environment, comprising uncontrollable power generators, uncontrollable loads, and multiple energy storage units. To address the challenge of minimizing energy loss in ESSs, this paper proposes a novel approach, called energy-efficient storage capacity with loss reduction (SCALE) scheme, that combines multiple-load power-flow assignment with a load-shifting algorithm to minimize energy loss and determine the optimal energy storage capacity. The optimization problem for optimal energy storage capacity is formalized using linear programming techniques. To validate the proposed scheme, real experimental data from a smart home environment during winter and summer seasons are employed. The results demonstrate the efficacy of the proposed algorithm in significantly reducing energy loss, particularly under winter conditions, and determining optimal energy storage capacity, with reductions of up to 11.4% in energy loss and up to 62.1% in optimal energy storage capacity. Full article

(This article belongs to the Special Issue Smart Home Design, 2nd Edition)

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12 pages, 6993 KB

Open AccessEditor’s ChoiceArticle

Experimental Tests of the Piston Axial Pump with Constant Pressure and Variable Flow

by Radovan Petrović, Andrzej Banaszek, Maja Andjelković, Hana R. Qananah and Khalefa A. Alnagasa

Designs 2024, 8(1), 5; https://doi.org/10.3390/designs8010005 - 30 Dec 2023

Cited by 5 | Viewed by 3185

Abstract

Constant pressure variable flow reciprocating axial pumps (CPAP) are used in various applications, where a constant output pressure is maintained when the flow rate changes. When the hydraulic system is at rated pressure or less, the swash plate has maximum tilt, and the [...] Read more.

Constant pressure variable flow reciprocating axial pumps (CPAP) are used in various applications, where a constant output pressure is maintained when the flow rate changes. When the hydraulic system is at rated pressure or less, the swash plate has maximum tilt, and the pump delivers maximum flow. The swash plate comes into this position thanks to the action of a reactive piston in which there are two springs. However, when the pressure rises above the nominal pressure value, the piston of the hydraulic pressure transducer (HPT) distributes the fluid under pressure to the hydraulic cylinder (HC), which causes a decrease in the tilt angle of the swash plate and a decrease in flow. The CPAP was selected as a component of the hydraulic system of the aircraft for the experimental tests in this paper. The experimental tests covered the structural and working parameters of the pump and analyzed their performance, efficiency and reliability. Experimental tests of structural and operating parameters of the CPAP were carried out in the Laboratory for Hydraulics and Pneumatics “PPT-Namenska” Trstenik on the hydraulic system, which simulated the real conditions prevailing in the hydraulic system of the aircraft. A system was used for data acquisition and recording of pump characteristics, which were obtained during experimental testing. The results of the measurement and testing of the structural parameters of the CPAP are shown in tabular form, and the experimental tests of static characteristics and dynamic behavior are shown diagrammatically. Full article

(This article belongs to the Section Mechanical Engineering Design)

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29 pages, 4284 KB

Open AccessEditor’s ChoiceArticle

Development and Performance Evaluation of Fibrous Pseudoplastic Quaternary Cement Systems for Aerial Additive Manufacturing

by Barrie Dams, Paul Shepherd and Richard J. Ball

Designs 2023, 7(6), 137; https://doi.org/10.3390/designs7060137 - 27 Nov 2023

Cited by 3 | Viewed by 2279

Abstract

Aerial additive manufacturing (AAM) represents a paradigm shift in using unmanned aerial vehicles (UAVs, often called ‘drones’) in the construction industry, using self-powered and untethered UAVs to extrude structural cementitious material. This requires miniaturisation of the deposition system. Rheological properties and known hydration [...] Read more.

Aerial additive manufacturing (AAM) represents a paradigm shift in using unmanned aerial vehicles (UAVs, often called ‘drones’) in the construction industry, using self-powered and untethered UAVs to extrude structural cementitious material. This requires miniaturisation of the deposition system. Rheological properties and known hydration times are important material parameters. Calcium aluminate cement (CAC) systems can be advantageous over purely ordinary Portland cement (OPC) binders as they promote hydration and increase early strength. A quaternary OPC/pulverised fuel ash (PFA)/CAC/calcium sulphate (CS) system was combined with polyvinyl alcohol (PVA) fibres and pseudoplastic hydrocolloids to develop a novel AAM material for miniaturised deposition. CAC hydration is affected by environmental temperature. Intending material to be extruded in situ, mixes were tested at multiple temperatures. OPC/PFA/CAC/CS mixes with PVA fibres were successfully extruded with densities of ≈1700 kg/m

^{3}

, yield stresses of 1.1–1.3 kPa and a compressive strength of 25 MPa. Pseudoplastic OPC/PFA/CAC/CS quaternary cementitious systems are demonstrated to be viable for AAM, provided mixes are modified with retarders as temperature increases. This study can significantly impact industry by demonstrating structural material which can be extruded using UAVs in challenging or elevated in situ construction, reducing safety risks. Full article

(This article belongs to the Special Issue Additive Manufacturing – Process Optimisation)

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22 pages, 8629 KB

Open AccessEditor’s ChoiceArticle

Rheological Behaviour of ABS/Metal Composites with Improved Thermal Conductivity for Additive Manufacturing

by Vicente F. Moritz, Harald Prévost, Janaína S. Crespo, Carlos A. Ferreira and Declan M. Devine

Designs 2023, 7(6), 133; https://doi.org/10.3390/designs7060133 - 17 Nov 2023

Cited by 2 | Viewed by 3025

Abstract

Metal-reinforced polymer composites are suitable materials for applications requiring special thermal, electrical or magnetic properties. Three-dimensional printing technologies enable these materials to be quickly shaped in any design directly and without the need for expensive moulds. However, processing data correlating specific information on [...] Read more.

Metal-reinforced polymer composites are suitable materials for applications requiring special thermal, electrical or magnetic properties. Three-dimensional printing technologies enable these materials to be quickly shaped in any design directly and without the need for expensive moulds. However, processing data correlating specific information on how the metal particles influence the rheological behaviour of such composites is lacking, which has a direct effect on the processability of these composites through melt processing additive manufacturing. This study reports the compounding and characterisation of ABS composites filled with aluminium and copper particulates. Experimental results demonstrated that the tensile modulus increased with the incorporation of metal particles; however, there was also an intense embrittling effect. Mechanical testing and rheological analysis indicated poor affinity between the fillers and matrix, and the volume fraction proved to be a crucial factor for complex viscosity, storage modulus and thermal conductivity. However, a promising set of properties was achieved, paving the way for polymer–metal composites with optimised processability, microstructure and properties in melt processing additive manufacturing. Full article

(This article belongs to the Special Issue Additive Manufacturing – Process Optimisation)

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26 pages, 7961 KB

Open AccessEditor’s ChoiceArticle

Field Experiment for a Prequalification Scheme for a Distribution System Operator on Distributed Energy Resource Aggregations

by Jung-Sung Park and Bal-Ho Kim

Designs 2023, 7(6), 134; https://doi.org/10.3390/designs7060134 - 17 Nov 2023

Cited by 1 | Viewed by 1802

Abstract

The purpose of this paper is to summarize and share the field experiment results of KEPCO’s project consortium to create a TSO-DSO-DERA interaction scheme. The field experiment was conducted based on the prequalification algorithm proposed in previous research from the same consortium, and [...] Read more.

The purpose of this paper is to summarize and share the field experiment results of KEPCO’s project consortium to create a TSO-DSO-DERA interaction scheme. The field experiment was conducted based on the prequalification algorithm proposed in previous research from the same consortium, and was designed to verify the validity of the algorithm under realistic grid conditions. In addition, during the course of the field experiment, it was found that points that were missed or not given much importance in the existing prequalification algorithm could affect the completeness of the overall system, and then practical improvements were made to improve this. The demonstration results confirm that the proposed algorithm is effective in real-world grid environments and can help DSOs to ensure the reliability of the distribution system while supporting DERA’s participation in the wholesale market using the proposed prequalification scheme. Full article

(This article belongs to the Collection Editorial Board Members’ Collection Series: Smart Energy Systems Design)

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20 pages, 4648 KB

Open AccessEditor’s ChoiceReview

A Review of the Current State of the Art of Polyether Ether Ketone (PEEK) Composite Based 3D-Printed Biomedical Scaffolds

by Rajesh Surendran, Sithara Sreenilayam Pavithran, Anugop Balachandran, Sony Vijayan, Kailasnath Madanan and Dermot Brabazon

Designs 2023, 7(6), 128; https://doi.org/10.3390/designs7060128 - 10 Nov 2023

Cited by 9 | Viewed by 4009

Abstract

Three-dimensional printing or additive manufacturing (AM) has enabled innovative advancements in tissue engineering through scaffold development. The use of scaffolds, developed by using AM technology for tissue repair (like cartilage and bone), could enable the growth of several cell types on the same [...] Read more.

Three-dimensional printing or additive manufacturing (AM) has enabled innovative advancements in tissue engineering through scaffold development. The use of scaffolds, developed by using AM technology for tissue repair (like cartilage and bone), could enable the growth of several cell types on the same implant. Scaffolds are 3D-printed using polymer-based composites. polyether ether ketone (PEEK)-based composites are ideal for scaffold 3D printing due to their excellent biocompatibility and mechanical properties resembling human bone. It is therefore considered to be the next-generation bioactive material for tissue engineering. Despite several reviews on the application of PEEK in biomedical fields, a detailed review of the recent progress made in the development of PEEK composites and the 3D printing of scaffolds has not been published. Therefore, this review focuses on the current status of technological developments in the 3D printing of bone scaffolds using PEEK-based composites. Furthermore, this review summarizes the challenges associated with the 3D printing of high-performance scaffolds based on PEEK composites. Full article

(This article belongs to the Special Issue Additive Manufacturing – Process Optimisation)

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25 pages, 3748 KB

Open AccessEditor’s ChoiceArticle

A Dynamic Matrix for the Study of Free Vibrations of Thin Circular Cylindrical Shells under Different Boundary Conditions

by Marco Cammalleri and Antonella Castellano

Designs 2023, 7(6), 122; https://doi.org/10.3390/designs7060122 - 26 Oct 2023

Cited by 4 | Viewed by 2526

Abstract

Although free vibrations of thin-walled cylinders have been extensively addressed in the relevant literature, finding a good balance between accuracy and simplicity of the procedures used for natural frequency assessment is still an open issue. This paper proposes a novel approach with a [...] Read more.

Although free vibrations of thin-walled cylinders have been extensively addressed in the relevant literature, finding a good balance between accuracy and simplicity of the procedures used for natural frequency assessment is still an open issue. This paper proposes a novel approach with a high potential for practical application for rapid esteem of natural frequencies of thin-walled cylinders under different boundary conditions. Starting from Donnell–Mushtari’s shell theory, the differential problem is simplified by using the principle of virtual work and introducing the flexural waveforms of a beam as constrained as the cylinder. Hence, the formulation is reduced to the eigenvalue problem of an equivalent 3 × 3 dynamic matrix, which depends on the cylinder geometry, material, and boundary conditions. Several comparisons with experimental, numerical, and analytical approaches are presented to prove model reliability and practical interest. An excellent balance between fast usability and accuracy is achieved. The user-friendliness of the model makes it suitable to be implemented during the design stage without requiring any deep knowledge of the topic. Full article

(This article belongs to the Section Civil Engineering Design)

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13 pages, 6229 KB

Open AccessEditor’s ChoiceArticle

Effect of Interference Size on Contact Pressure Distribution of Railway Wheel Axle Press Fitting

by Kitesa Akewaq Irena, Hirpa G. Lemu and Yahiya Ahmed Kedir

Designs 2023, 7(5), 119; https://doi.org/10.3390/designs7050119 - 22 Oct 2023

Cited by 4 | Viewed by 5942

Abstract

Mechanical couplings in engineering usually use interference fits to connect the shaft and hub. A railway wheel axle is a press fit that is connected by interference and can be subjected to bending stress. In loaded press fits, a high concentration of contact [...] Read more.

Mechanical couplings in engineering usually use interference fits to connect the shaft and hub. A railway wheel axle is a press fit that is connected by interference and can be subjected to bending stress. In loaded press fits, a high concentration of contact stresses can be generated in the area of the axle-fillet beam, which in most cases leads to the failure of the axle due to fatigue and fretting fatigues. Therefore, it is crucial to determine the ability of the press-fitted joints to provide sufficient frictional resistance that can withstand the loads and torques by evaluating the safety factor, especially when the mechanical or structural system is loaded. In this paper, the contact pressure and stress distribution along the radius of the wheel axle are studied using the analytical calculation of Lame’s equation, and the numerical method used is by ANSYS software. It was found that interference fits have a great influence on the connection strength of interference fits, which are directly related to the contact pressure. Increasing the interference increases the contact pressure, which allows higher torque and load capacity to be transmitted. The finite element analysis showed good agreement for the highest interference value of 230 µm with a relative error of 1.4%, while this error increased to the maximum relative error of 14.33% for a minimum interference of 100 µm. Full article

(This article belongs to the Section Mechanical Engineering Design)

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18 pages, 4747 KB

Open AccessEditor’s ChoiceArticle

3D Printed Voronoi Structures Inspired by Paracentrotus lividus Shells

by Alexandros Efstathiadis, Ioanna Symeonidou, Konstantinos Tsongas, Emmanouil K. Tzimtzimis and Dimitrios Tzetzis

Designs 2023, 7(5), 113; https://doi.org/10.3390/designs7050113 - 29 Sep 2023

Cited by 11 | Viewed by 2640

Abstract

The present paper investigates the mechanical behavior of a biomimetic Voronoi structure, inspired by the microstructure of the shell of the sea urchin Paracentrotus lividus, with its characteristic topological attributes constituting the technical evaluation stage of a novel biomimetic design strategy. A [...] Read more.

The present paper investigates the mechanical behavior of a biomimetic Voronoi structure, inspired by the microstructure of the shell of the sea urchin Paracentrotus lividus, with its characteristic topological attributes constituting the technical evaluation stage of a novel biomimetic design strategy. A parametric design algorithm was used as a basis to generate design permutations with gradually increasing rod thickness, node count, and model smoothness, geometric parameters that define a Voronoi structure and increase its relative density as they are enhanced. Physical PLA specimens were manufactured with a fused filament fabrication (FFF) printer and subjected to quasi-static loading. Finite element analysis (FEA) was conducted in order to verify the experimental results. A minor discrepancy between the relative density of the designed and printed models was calculated. The tests revealed that the compressive behavior of the structure consists of an elastic region followed by a smooth plateau region and, finally, by the densification zone. The yield strength, compressive modulus, and plateau stress of the structure are improved as the specific geometric parameters are enhanced. The same trend is observed in the energy absorption capabilities of the structure while a reverse one characterizes the densification strain of the specimens. A second-degree polynomial relation is also identified between the modulus, plateau stress, and energy capacity when plotted against the relative density of the specimens. Distinct Voronoi morphologies can be acquired with similar mechanical characteristics, depending on the design requirements and application. Potential applications include lightweight structural materials and protective gear and accessories. Full article

(This article belongs to the Collection Editorial Board Members’ Collection Series: Biomaterials Design)

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36 pages, 455 KB

Open AccessEditor’s ChoiceArticle

Enhancing Disassembly Practices for Electric Vehicle Battery Packs: A Narrative Comprehensive Review

by Matteo Beghi, Francesco Braghin and Loris Roveda

Designs 2023, 7(5), 109; https://doi.org/10.3390/designs7050109 - 22 Sep 2023

Cited by 24 | Viewed by 8262

Abstract

In the context of current societal challenges, such as climate neutrality, industry digitization, and circular economy, this paper addresses the importance of improving recycling practices for electric vehicle (EV) battery packs, with a specific focus on lithium–ion batteries (LIBs). To achieve this, the [...] Read more.

In the context of current societal challenges, such as climate neutrality, industry digitization, and circular economy, this paper addresses the importance of improving recycling practices for electric vehicle (EV) battery packs, with a specific focus on lithium–ion batteries (LIBs). To achieve this, the paper conducts a systematic review (using Google Scholar, Scopus, and Web of Science as search engines), considering the last 10 years, to examine existing recycling methods, robotic/collaborative disassembly cells, and associated control techniques. The aim is to provide a comprehensive and detailed review that can serve as a valuable resource for future research in the industrial domain. By analyzing the current state of the field, this review identifies emerging needs and challenges that need to be addressed for the successful implementation of automatic robotic disassembly cells for end-of-life (EOL) electronic products, such as EV LIBs. The findings presented in this paper enhance our understanding of recycling practices and lay the groundwork for more precise research directions in this important area. Full article

(This article belongs to the Special Issue Battery System Design)

28 pages, 9894 KB

Open AccessEditor’s ChoiceArticle

Design and Considerations: Microelectromechanical System (MEMS) Vibrating Ring Resonator Gyroscopes

by Waqas Amin Gill, Ian Howard, Ilyas Mazhar and Kristoffer McKee

Designs 2023, 7(5), 106; https://doi.org/10.3390/designs7050106 - 11 Sep 2023

Cited by 8 | Viewed by 3585

Abstract

Microelectromechanical system (MEMS) vibrating gyroscope design considerations are always intriguing due to their microscale mechanical, electrical, and material behavior. MEMS vibrating ring gyroscopes have become important inertial sensors in inertial measurement units (IMU) for navigation and sensing applications. The design of a MEMS [...] Read more.

Microelectromechanical system (MEMS) vibrating gyroscope design considerations are always intriguing due to their microscale mechanical, electrical, and material behavior. MEMS vibrating ring gyroscopes have become important inertial sensors in inertial measurement units (IMU) for navigation and sensing applications. The design of a MEMS vibrating ring gyroscope incorporates an oscillating ring structure as a proof mass, reflecting unique design challenges and possibilities. This paper presents a comprehensive design analysis of the MEMS vibrating ring gyroscope from the mechanical, electrical, and damping perspectives. The mechanical design of the MEMS vibrating ring gyroscope investigates the various frame designs of the vibrating ring structure, as well as the various beam structures, including rectangular and semicircular beam structures, which are analyzed using mathematical models and finite element analysis (FEA) simulations that provide an in-depth analysis of the stiffness and deflection of the vibrating structures. The electrical designs of the MEMS vibrating ring gyroscope are analyzed using various electrode configurations, electrostatic actuation, and capacitive detection mechanisms. The design analysis of various forms of damping, including viscous, structural, thermoelastic, and anchor damping, is discussed. The variety of design structures is investigated for MEMS vibrating ring gyroscopes’ mechanical, electrical, and damping performance. Full article

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31 pages, 2386 KB

Open AccessEditor’s ChoiceReview

The Status of On-Board Hydrogen Storage in Fuel Cell Electric Vehicles

by Julián A. Gómez and Diogo M. F. Santos

Designs 2023, 7(4), 97; https://doi.org/10.3390/designs7040097 - 2 Aug 2023

Cited by 45 | Viewed by 15762

Abstract

Hydrogen as an energy carrier could help decarbonize industrial, building, and transportation sectors, and be used in fuel cells to generate electricity, power, or heat. One of the numerous ways to solve the climate crisis is to make the vehicles on our roads [...] Read more.

Hydrogen as an energy carrier could help decarbonize industrial, building, and transportation sectors, and be used in fuel cells to generate electricity, power, or heat. One of the numerous ways to solve the climate crisis is to make the vehicles on our roads as clean as possible. Fuel cell electric vehicles (FCEVs) have demonstrated a high potential in storing and converting chemical energy into electricity with zero carbon dioxide emissions. This review paper comprehensively assesses hydrogen’s potential as an innovative alternative for reducing greenhouse gas (GHG) emissions in transportation, particularly for on-board applications. To evaluate the industry’s current status and future challenges, the work analyses the technology behind FCEVs and hydrogen storage approaches for on-board applications, followed by a market review. It has been found that, to achieve long-range autonomy (over 500 km), FCEVs must be capable of storing 5–10 kg of hydrogen in compressed vessels at 700 bar, with Type IV vessels being the primary option in use. Carbon fiber is the most expensive component in vessel manufacturing, contributing to over 50% of the total cost. However, the cost of FCEV storage systems has considerably decreased, with current estimates around 15.7 $/kWh, and is predicted to drop to 8 $/kWh by 2030. In 2021, Toyota, Hyundai, Mercedes-Benz, and Honda were the major car brands offering FCEV technology globally. Although physical and chemical storage technologies are expected to be valuable to the hydrogen economy, compressed hydrogen storage remains the most advanced technology for on-board applications. Full article

(This article belongs to the Collection Editorial Board Members’ Collection Series: Smart Energy Systems Design)

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25 pages, 2046 KB

Open AccessEditor’s ChoiceArticle

A Unit-Load Approach for Reliability-Based Design Optimization of Linear Structures under Random Loads and Boundary Conditions

by Robert James Haupin and Gene Jean-Win Hou

Designs 2023, 7(4), 96; https://doi.org/10.3390/designs7040096 - 2 Aug 2023

Cited by 2 | Viewed by 2024

Abstract

The low order Taylor’s series expansion was employed in this study to estimate the reliability indices of the failure criteria for reliability-based design optimization of a linear static structure subjected to random loads and boundary conditions. By taking the advantage of the linear [...] Read more.

The low order Taylor’s series expansion was employed in this study to estimate the reliability indices of the failure criteria for reliability-based design optimization of a linear static structure subjected to random loads and boundary conditions. By taking the advantage of the linear superposition principle, only a few analyses of the structure subjected to unit-loads are needed through the entire optimization process to produce acceptable results. Two structural examples are presented in this study to illustrate the effectiveness of the proposed approach for reliability-based design optimization: one deals with a truss structure subjected to random multiple point constraints, and the other conducts shape design optimization of a plane stress problem subjected to random point loads. Both examples were formulated and solved by the finite element method. The first example used the penalty method to reformulate the multiple point constraints as external loads, while the second example introduced an approach to propagate the uncertainty linearly from the nodal displacement vector to the nodal von Mises stress vector. The final designs obtained from the reliability-based design optimization were validated through Monte Carlo simulation. This validation process was completed with only four unit-load analyses for the first example and two for the second example. Full article

(This article belongs to the Special Issue Design Sensitivity Analysis and Engineering Optimization)

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35 pages, 17261 KB

Open AccessEditor’s ChoiceArticle

Peltier Cell Integration in Packaging Design for Minimizing Energy Consumption and Temperature Variation during Refrigerated Transport

by Pedro Fernandes, Pedro D. Gaspar and Pedro D. Silva

Designs 2023, 7(4), 88; https://doi.org/10.3390/designs7040088 - 4 Jul 2023

Viewed by 3554

Abstract

This study proposes an innovative approach to reduce temperature fluctuations in refrigerated transport during loading and unloading, aiming to minimize food waste and optimize energy consumption in the food supply chain. The solution involves integrating Peltier cells into secondary and tertiary packaging to [...] Read more.

This study proposes an innovative approach to reduce temperature fluctuations in refrigerated transport during loading and unloading, aiming to minimize food waste and optimize energy consumption in the food supply chain. The solution involves integrating Peltier cells into secondary and tertiary packaging to improve system efficiency and minimize temperature variations. Four distinct tests were conducted: a reference test, continuous Peltier system operation, and two intermittent cooling tests for the hot side of the cells. The results highlight the effectiveness of this approach, particularly in the fourth test where the average final food temperature decreased from 3.2 °C (reference test) to 2.8 °C. Integrating Peltier cells into packaging shows potential benefits in minimizing food waste, reducing energy consumption, and associated emissions during refrigerated transport. This research contributes to the sustainable design and manufacturing of packaging systems, specifically in the context of refrigerated transport. By maintaining a consistent temperature environment during the critical loading and unloading phases, incorporating Peltier cells enhances the overall performance and efficiency of refrigerated transport system. These results point out the significance of exploring innovative solutions for sustainable food preservation and the decrease of waste all along the food supply chain. Full article

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32 pages, 4311 KB

Open AccessEditor’s ChoiceReview

Design for Additive Manufacturing: Recent Innovations and Future Directions

by Paul F. Egan

Designs 2023, 7(4), 83; https://doi.org/10.3390/designs7040083 - 29 Jun 2023

Cited by 31 | Viewed by 12648

Abstract

Design for additive manufacturing (DfAM) provides a necessary framework for using novel additive manufacturing (AM) technologies for engineering innovations. Recent AM advances include shaping nickel-based superalloys for lightweight aerospace applications, reducing environmental impacts with large-scale concrete printing, and personalizing food and medical devices [...] Read more.

Design for additive manufacturing (DfAM) provides a necessary framework for using novel additive manufacturing (AM) technologies for engineering innovations. Recent AM advances include shaping nickel-based superalloys for lightweight aerospace applications, reducing environmental impacts with large-scale concrete printing, and personalizing food and medical devices for improved health. Although many new capabilities are enabled by AM, design advances are necessary to ensure the technology reaches its full potential. Here, DfAM research is reviewed in the context of Fabrication, Generation, and Assessment phases that bridge the gap between AM capabilities and design innovations. Materials, processes, and constraints are considered during fabrication steps to understand AM capabilities for building systems with specified properties and functions. Design generation steps include conceptualization, configuration, and optimization to drive the creation of high-performance AM designs. Assessment steps are necessary for validating, testing, and modeling systems for future iterations and improvements. These phases provide context for discussing innovations in aerospace, automotives, construction, food, medicine, and robotics while highlighting future opportunities for design services, bio-inspired design, fabrication robots, and machine learning. Overall, DfAM has positively impacted diverse engineering applications, and further research has great potential for driving new developments in design innovation. Full article

(This article belongs to the Special Issue Additive Manufacturing – Process Optimisation)

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35 pages, 13372 KB

Open AccessEditor’s ChoiceArticle

A Structural and Thermal Comparative Review of 3D-Printed Wall Shapes

by Nicholas D. Bello and Ali M. Memari

Designs 2023, 7(3), 80; https://doi.org/10.3390/designs7030080 - 19 Jun 2023

Cited by 3 | Viewed by 2810

Abstract

This article explores several aspects of the three-dimensional concrete printing (3DCP) industry. More specifically, it begins with a literature review discussing the background of this technology. This literature review also explores several of the challenges that the industry is currently facing. In this [...] Read more.

This article explores several aspects of the three-dimensional concrete printing (3DCP) industry. More specifically, it begins with a literature review discussing the background of this technology. This literature review also explores several of the challenges that the industry is currently facing. In this way, a knowledge gap is identified. More specifically, there are few studies that have explored the structural and thermal performance of typical walls printed in this industry. Therefore, we used the simulation tool in SolidWorks to examine the structural behavior of several different wall types when pressure was applied to the exterior face. In addition to this, the thermal performance of different wall types was also studied in SolidWorks by applying a temperature difference between the exterior and interior faces of each wall. For example, one wall shape in this study had minimum factor of safety of approximately 100 due when a load was applied, and the same wall lost approximately 212 W due to the temperature difference applied in this study. Finally, SolidWorks was used to calculate the moment of inertia of the cross sections of several of these walls, which helped to provide a better understanding of each wall’s structural rigidity. Full article

(This article belongs to the Special Issue Additive Manufacturing – Process Optimisation)

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29 pages, 3121 KB

Open AccessEditor’s ChoiceReview

Electricity Pricing and Its Role in Modern Smart Energy System Design: A Review

by Jiaqi Liu, Hongji Hu, Samson S. Yu and Hieu Trinh

Designs 2023, 7(3), 76; https://doi.org/10.3390/designs7030076 - 16 Jun 2023

Cited by 8 | Viewed by 5773

Abstract

Energy is the foundation for human survival and socio-economic development, and electricity is a key form of energy. Electricity prices are a key factor affecting the interests of various stakeholders in the electricity market, playing a significant role in the sustainable development of [...] Read more.

Energy is the foundation for human survival and socio-economic development, and electricity is a key form of energy. Electricity prices are a key factor affecting the interests of various stakeholders in the electricity market, playing a significant role in the sustainable development of energy and the environment. As the number of distributed energy resources (DERs) increases, today’s power systems no longer rely on a vertical market model and fixed electricity pricing scheme but instead depend on power dispatch and dynamic pricing to match supply and demand. This can help prevent significant fluctuations in supply–load imbalance and maintain system stability. Modern power grids have evolved by integrating information, communication, and intelligent control technologies with traditional power systems, giving rise to the concept of smart electric grids. Choosing an appropriate pricing scheme to manage large-scale DERs and controllable loads in today’s power grid become very important. However, the existing literature lacks a comprehensive review of electricity pricing in power systems and its transformative impact on shaping the energy landscape. To fill this void, this paper provides a survey on the developments, methods, and frameworks related to electricity pricing and energy trading. The review mainly considers the development of pricing in a centralized power grid, peer-to-peer (P2P) and microgrid-to-microgrid (M2M) energy trading and sharing, and various pricing methods. The review will cover the pricing schemes in modern power systems, particularly with respect to renewable energy sources (RESs) and batteries, as well as controllable load applications, and the impact of pricing schemes based on demand-side ancillary services (DSAS) for grid frequency support. Lastly, this review article describes the current frameworks and limitations of electricity pricing in the current energy market, as well as future research directions. This review should offer a great overview and deep insights into today’s electricity market and how pricing methods will drive and facilitate the future establishment of smart energy systems. Full article

(This article belongs to the Collection Editorial Board Members’ Collection Series: Smart Energy Systems Design)

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23 pages, 11598 KB

Open AccessEditor’s ChoiceArticle

From Meaning to Expression: A Dual Approach to Coupling

by Lukas Van Campenhout, Ward Vancoppenolle and Ivo Dewit

Designs 2023, 7(3), 69; https://doi.org/10.3390/designs7030069 - 23 May 2023

Cited by 4 | Viewed by 2482

Abstract

Coupling is a key concept in the field of embodied interaction with digital products and systems, describing how digital phenomena relate to the physical world. In this paper, we present a Research through Design process in which the concept of coupling is explored [...] Read more.

Coupling is a key concept in the field of embodied interaction with digital products and systems, describing how digital phenomena relate to the physical world. In this paper, we present a Research through Design process in which the concept of coupling is explored and deepened. The use case that we employed to conduct our research is an industrial workplace proposed by Audi Brussels and Kuka. Our aim was to enrich this workplace with projection, or Spatial Augmented Reality, while focusing on operator interaction. We went through three successive design iterations, each of which resulted in a demonstrator. We present each of the three demonstrators, focusing on how they propelled our understanding of coupling. We establish a framework in which coupling between different events, be they physical or digital, emerges on four different aspects: time, location, direction, and expression. We bring the first three aspects together under one heading—coupling of meaning—and relate it to ease of use and pragmatic usability. We uncover the characteristics of the fourth aspect—coupling of expression—and link it to the psychological wellbeing of the operator in the workplace. We conclude this paper by highlighting its contribution to the embodied interaction research agenda. Full article

(This article belongs to the Special Issue Mixture of Human and Machine Intelligence in Digital Manufacturing)

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18 pages, 799 KB

Open AccessEditor’s ChoiceArticle

Minimum-Lap-Time Planning of Multibody Vehicle Models via the Articulated-Body Algorithm

by Marcello Domenighini, Lorenzo Bartali, Eugeniu Grabovic and Marco Gabiccini

Designs 2023, 7(3), 65; https://doi.org/10.3390/designs7030065 - 17 May 2023

Cited by 4 | Viewed by 3674

Abstract

Minimum lap-time planning (MLTP) is a well-established problem in the race car industry to provide guidelines for drivers and optimize the vehicle’s setup. In this paper, we tackle the 3D nature of the problem in its full extension, making no simplifying assumptions on [...] Read more.

Minimum lap-time planning (MLTP) is a well-established problem in the race car industry to provide guidelines for drivers and optimize the vehicle’s setup. In this paper, we tackle the 3D nature of the problem in its full extension, making no simplifying assumptions on the mechanics of the system. We propose a multibody vehicle model, described by rigorous dynamical equations. To effectively handle the resulting complexity, we devised an efficient direct dynamics computational method based on Featherstone’s articulated-body algorithm (ABA). To solve the MLTP, we employed a direct-collocation technique, discretizing the problem so that all information of the 3D track is pre-processed and directly embedded into the discrete problem. This discretization approach turns out to be perfectly compatible with our vehicle model, leading to a solution in accessible computational time frames. The high level of detail of the model makes the proposed approach most useful for in-depth vehicle dynamics analyses on complex tracks. To substantiate the analysis, we provide a comparison with the results obtained by a double-track model on the Nürburgring Nordschleife circuit. Consistently with the average trend defined by the double track, the proposed model features a more dynamically rich behavior, realistically capturing the higher-order effects elicited by the sharp corners and the highly variable slope of the track. Full article

(This article belongs to the Section Smart Manufacturing System Design)

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19 pages, 3162 KB

Open AccessEditor’s ChoiceArticle

Designing and Testing a Tool That Connects the Value Proposition of Deep-Tech Ventures to SDGs

by Joppe Schutselaars, A. Georges L. Romme, John Bell, Annelies S. A. Bobelyn and Robin van Scheijndel

Designs 2023, 7(2), 50; https://doi.org/10.3390/designs7020050 - 26 Mar 2023

Cited by 7 | Viewed by 5587

Abstract

Deep-tech startups have enormous potential to solve major societal challenges, but their failure rates are quite high (above 90%). In this respect, deep-tech systems and products have long development times and thus require substantial amounts of investment capital long before the first customer [...] Read more.

Deep-tech startups have enormous potential to solve major societal challenges, but their failure rates are quite high (above 90%). In this respect, deep-tech systems and products have long development times and thus require substantial amounts of investment capital long before the first customer can be served. Moreover, potential investors increasingly expect that the value proposition of a deep-tech venture has a clear sustainability dimension. We therefore designed a tool that serves to develop a convincing value proposition for investors, one that is explicitly connected to the Sustainable Development Goals (SDGs) of the United Nations. We adopted a design science approach to develop and test this tool in the context of a deep-tech venture builder located in the Netherlands. The final tool arising from this study extends and integrates various existing tools with an explicit connection to the SDGs. As such, this tool enables deep-tech entrepreneurs to develop a value proposition that is more likely to attract early-stage investors. Full article

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13 pages, 3513 KB

Open AccessEditor’s ChoiceArticle

On Liquid Flow Maldistribution through Investigation of Random Open-Structure Packings

by Daniela Dzhonova-Atanasova, Konstantina Stefanova and Svetoslav Nakov

Designs 2023, 7(2), 47; https://doi.org/10.3390/designs7020047 - 24 Mar 2023

Cited by 1 | Viewed by 2562

Abstract

The optimal design of packed columns for separation processes is strongly dependent on an accurate prediction of the fluid flows in the packing. Insufficient knowledge about the complex factors and mechanisms governing hydrodynamic effects is compensated for by empirical information. The present study [...] Read more.

The optimal design of packed columns for separation processes is strongly dependent on an accurate prediction of the fluid flows in the packing. Insufficient knowledge about the complex factors and mechanisms governing hydrodynamic effects is compensated for by empirical information. The present study fills the gap in experimental data about the liquid phase distribution in plastic Raschig Super-Ring (RSRP) packing and plastic Ralu–Flow (RF) packing. These belong to the family of widely used random packings with an open lattice structure characterized by high mass transfer efficiency and a low pressure drop. The study was performed using the liquid collection method with a device with concentric annular collection sections at the packing outlet. Large-scale liquid maldistribution in the central and peripheral zones of the packed bed were evaluated in comparison data on competing random and structured packings. The effects of the packing size and the liquid load on the radial distribution of the superficial liquid velocity, wall flow formation and the maldistribution factor were investigated and analyzed. The results contribute to deepening the knowledge about the phenomenon of large-scale liquid flow maldistribution in packed columns, as well as to design enhancement. Full article

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22 pages, 4421 KB

Open AccessEditor’s ChoiceArticle

Water Pumping System Supplied by a PV Generator and with a Switched Reluctance Motor Using a Drive Based on a Multilevel Converter with Reduced Switches

by Vitor Fernão Pires, Daniel Foito, Armando Cordeiro, Tito G. Amaral, Hao Chen, Armando Pires and João F. Martins

Designs 2023, 7(2), 39; https://doi.org/10.3390/designs7020039 - 3 Mar 2023

Cited by 4 | Viewed by 2676

Abstract

Pumping systems play a fundamental role in many applications. One of the applications in which these systems are very important is to pump water. However, in the real world context, the use of renewable energies to supply this kind of system becomes essential. [...] Read more.

Pumping systems play a fundamental role in many applications. One of the applications in which these systems are very important is to pump water. However, in the real world context, the use of renewable energies to supply this kind of system becomes essential. Thus, this paper proposes a water pumping system powered by a photovoltaic (PV) generator. In addition, due to its interesting characteristics, such low manufacturing cost, free of rare-earth elements, simple design and robustness for pumping systems, a switched reluctance motor (SRM) is used. The power electronic system to be used in the PV generator and to control the SRM consists of a DC/DC converter with a bipolar output and a multilevel converter. The adopted DC/DC converter uses only one switch, so its topology can be considered as a derivation of the combination of a Zeta converter with a buck–boost converter. Another important aspect is that this converter allows continuous input current, which is desirable for PV panels. The topology selected to control the SRM is a multilevel converter. This proposed topology was adopted with the purpose of reducing the number of power semiconductors. A maximum power point algorithm (MPPT) associated with the DC/DC converter to obtain the maximum power of the PV panels is also proposed. This MPPT will be developed based on the concept of the time derivative of the power and voltage. It will be verified that with the increase in solar irradiance, the generated power will also increase. From this particular case study, it will be verified that changes in the irradiance from 1000 W/m² to 400 W/m² will correspond to a change in the motor speed from 1220 rpm to 170 rpm. The characteristics and operation of the proposed system will be verified through several simulation and experimental studies. Full article

(This article belongs to the Topic Advanced Electrical Machines and Drives Technologies)

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30 pages, 8014 KB

Open AccessEditor’s ChoiceArticle

Automated Solar PV Simulation System Supported by DC–DC Power Converters

by Armando Cordeiro, Miguel Chaves, Paulo Gâmboa, Filipe Barata, Pedro Fonte, Hélio Lopes, Vítor Fernão Pires, Daniel Foito, Tito G. Amaral and João Francisco Martins

Designs 2023, 7(2), 36; https://doi.org/10.3390/designs7020036 - 1 Mar 2023

Cited by 5 | Viewed by 3618

Abstract

Solar photovoltaic simulators are valuable tools for the design and evaluation of several components of photovoltaic systems. They can also be used for several purposes, such as educational objectives regarding operation principles, control strategies, efficiency, maintenance, and other aspects. This paper presents an [...] Read more.

Solar photovoltaic simulators are valuable tools for the design and evaluation of several components of photovoltaic systems. They can also be used for several purposes, such as educational objectives regarding operation principles, control strategies, efficiency, maintenance, and other aspects. This paper presents an automated solar photovoltaic simulation system with the capability to generate automated tests considering different parameters of solar photovoltaic panels and different operation conditions. The proposed simulator is composed of three buck-boost DC–DC power converters controlled in such a way that will behave similarly to solar photovoltaic panels. It allows to introduce additional variable loads and maximum power point tracker algorithms similar to real systems. Some converters are controlled by a DSP microcontroller connected to a single programmable logic controller which generates the automated tests. Thus, using the presented solution, it is possible to implement the I-V and P-V characteristic curves of solar photovoltaic panels and evaluate different maximum power point tracker algorithms considering different meteorological conditions and load variations, being a useful tool to teach subjects related to renewable energy sources and related applications. Several simulation results using Matlab/Simulink and experimental results are presented to validate the operation of the proposed solution. Experimental results achieve a ripple between 2% and 5% of the desired average current in MPP conditions. Full article

(This article belongs to the Topic Power Electronics Converters)

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22 pages, 6368 KB

Open AccessFeature PaperEditor’s ChoiceArticle

Open-Source Vertical Swinging Wood-Based Solar Photovoltaic Racking Systems

by Nicholas Vandewetering, Koami Soulemane Hayibo and Joshua M. Pearce

Designs 2023, 7(2), 34; https://doi.org/10.3390/designs7020034 - 22 Feb 2023

Cited by 16 | Viewed by 4887

Abstract

Vertical bifacial solar photovoltaic (PV) racking systems offer the opportunity for large-scale agrivoltaics to be employed at farms producing field crops with conventional farming equipment. Unfortunately, commercial proprietary vertical racks cost more than all types of conventional PV farm racking solutions. To overcome [...] Read more.

Vertical bifacial solar photovoltaic (PV) racking systems offer the opportunity for large-scale agrivoltaics to be employed at farms producing field crops with conventional farming equipment. Unfortunately, commercial proprietary vertical racks cost more than all types of conventional PV farm racking solutions. To overcome these cost barriers, this study reports on the development of a new wood-based PV racking design. The open-source design consists of a hinge mechanism, which reduces mechanical loading and enables wood to be used as the main structural material, and is the first of its kind. This open-source vertical wood-based PV rack is (i) constructed from locally accessible (domestic) renewable and sustainable materials, (ii) able to be made with hand tools by the average farmer on site, (iii) possesses a 25-year lifetime to match PV warranties, and (iv) is structurally sound, following Canadian building codes to weather high wind speeds and heavy snow loads. The results showed that the capital cost of the racking system is less expensive than the commercial equivalent and all of the previous wood-based rack designs, at a single unit retail cost of CAD 0.21. The racking LCOE is 77% of the cost of an equivalent commercial racking system using retail small-scale component costs, and is 22%, 34%, and 38% less expensive than commercial metal vertical racking, wood fixed tilt racking, and wood seasonal tilt racking costs, respectively. Overall, wooden vertical swinging PV racking provides users with a low-cost, highly available alternative to conventional metal vertical racking, along with a potential increase in energy yield in high wind areas thanks to its unique swinging mechanism. Full article

(This article belongs to the Section Smart Manufacturing System Design)

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11 pages, 3452 KB

Open AccessEditor’s ChoiceArticle

Bio-lubricant Properties Analysis of Drilling an Innovative Design of Bioactive Kinetic Screw into Bone

by Carlos Aurelio Andreucci, Elza M. M. Fonseca and Renato N. Jorge

Designs 2023, 7(1), 21; https://doi.org/10.3390/designs7010021 - 1 Feb 2023

Cited by 11 | Viewed by 2934

Abstract

Biotribology is applied to study the friction, wear, and lubrication of biological systems or natural phenomena under relative motion in the human body. It is a multidisciplinary field and tribological processes impact all aspects of our daily life. Tribological processes may occur after [...] Read more.

Biotribology is applied to study the friction, wear, and lubrication of biological systems or natural phenomena under relative motion in the human body. It is a multidisciplinary field and tribological processes impact all aspects of our daily life. Tribological processes may occur after the implantation of an artificial device in the human body with a wide variety of sliding and frictional interfaces. Blood is a natural bio-lubricant experiencing laminar flow at the lower screw velocities associated with drilling implants into bone, being a viscoelastic fluid with viscous and fluid characteristics. The viscosity comes from the blood plasma, while the elastic properties are from the deformation of red blood cells. In this study, drilling parameters according to material properties obtained by Finite Element Analysis are given. The influence of blood on the resulting friction between the surfaces is demonstrated and correlated with mechanical and biological consequences, identifying an innovative approach to obtaining a new lubricant parameter for bone drilling analysis. The lubrication parameter (HN) found within the limitations of conditions used in this study is 10.7 × 10⁻⁷ for both cortical bone (D1) and spongy bone (D4). A thermal-structural analysis of the densities of the soft bone (D4) and hard bone (D1) shows differences in only the equivalent stress values due to the differences in respective Young moduli. The natural occurrences of blood as a lubricant in bone-screw perforations are poorly investigated in the literature and its effects are fundamental in osseointegration. This work aims to elucidate the relevance of the study of blood as a lubricant in drilling and screwing implants into bone at lower speeds. Full article

(This article belongs to the Collection Editorial Board Members’ Collection Series: Biomaterials Design)

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19 pages, 1562 KB

Open AccessEditor’s ChoiceArticle

Design and Implementation of Reinforcement Learning for Automated Driving Compared to Classical MPC Control

by Ahmad Reda and József Vásárhelyi

Designs 2023, 7(1), 18; https://doi.org/10.3390/designs7010018 - 29 Jan 2023

Cited by 6 | Viewed by 3774

Abstract

Many classic control approaches have already proved their merits in the automotive industry. Model predictive control (MPC) is one of the most commonly used methods. However, its efficiency drops off with increase in complexity of the driving environment. Recently, machine learning methods have [...] Read more.

Many classic control approaches have already proved their merits in the automotive industry. Model predictive control (MPC) is one of the most commonly used methods. However, its efficiency drops off with increase in complexity of the driving environment. Recently, machine learning methods have been considered an efficient alternative to classical control approaches. Even with successful implementation of reinforcement learning in real-world applications, it is still not commonly used compared to supervised and unsupervised learning. In this paper, a reinforcement learning (RL)-based framework is suggested for application in autonomous driving systems to maintain a safe distance. Additionally, an MPC-based control model is designed for the same task. The behavior of the two controllers is compared and discussed. The trained RL model was deployed on a low-end FPGA-in-the-loop (field-programmable gate array in-the-loop). The results showed that the two controllers responded efficiently to changes in the environment. Specifically, the response of the RL controller was faster, at approximately 1.75 s, than that of the MPC controller, while the MPC provided better overshooting performance (approximately 1.3 m/s less) in terms of following the reference speeds. The reinforcement-learning model showed efficient behavior after being deployed on the FPGA with (

4.9 \times 10^{- 6})

m

^{2} /

s as a maximum deviation compared to MATLAB Simulink. Full article

(This article belongs to the Topic Advanced Electric Vehicle Technology)

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13 pages, 10718 KB

Open AccessEditor’s ChoiceArticle

Verification of Finger Positioning Accuracy of an Affordable Transradial Prosthesis

by Zuzana Koudelkova, Ales Mizera, Michaela Karhankova, Vaclav Mach, Pavel Stoklasek, Matej Krupciak, Jan Minarcik and Roman Jasek

Designs 2023, 7(1), 14; https://doi.org/10.3390/designs7010014 - 16 Jan 2023

Cited by 9 | Viewed by 3880

Abstract

Whether due to unpleasant events, injuries or illnesses, people lose the mobility of their hands. In extreme cases, amputation of the hand or hands can also occur. This paper deals with designing and fabricating an affordable transradial prosthesis using 3D printing and measuring [...] Read more.

Whether due to unpleasant events, injuries or illnesses, people lose the mobility of their hands. In extreme cases, amputation of the hand or hands can also occur. This paper deals with designing and fabricating an affordable transradial prosthesis using 3D printing and measuring finger positioning accuracy during a long-term test. The prosthesis’ design was inspired by the tested wire construction used in both low-cost commercial and do-it-yourself prostheses. The shape of the partial parts of the prosthesis was adapted for production using 3D printing. A high priority was also placed on using as few electronics as possible, while the used electronics also has to be affordable. Six MG995 servo motors were utilized to provide movement for the fingers, thumbs and wrist, and an Arduino Nano R3 was used to control their function. A control glove was subsequently developed to control the prosthesis, allowing accurate measurement of the angles of the finger’s distal phalanges. Their measured angle served as a reference for matching the angles on the prosthetic hand. To verify the prosthesis’s durability and the finger grip’s accuracy, a long-term test of 100,000 cycles, which repeated the western world’s finger-counting system from 0 to 5, was performed. It was determined that there is only a minor deviation from the initial finger position based on measurements of the accuracy of the finger position before and after the long-term test. Only minimal wear of functional parts after the long-term test was observed. No significant deviations from the desired finger angles were measured. Full article

(This article belongs to the Section Bioengineering Design)

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16 pages, 6688 KB

Open AccessEditor’s ChoiceArticle

Design and Manufacturing Process of a New Type of Deep-Sea Spherical Pressure Hull Structure

by Yang Jing, Chenghai Kong, Jingchao Guan, Wei Zhao, Apollo B. Fukuchi and Xilu Zhao

Designs 2023, 7(1), 12; https://doi.org/10.3390/designs7010012 - 11 Jan 2023

Cited by 3 | Viewed by 7413

Abstract

Spherical shell structures are the most suitable shape for deep-sea pressure hulls because they have ideal mechanical properties for handling symmetrical pressure. However, the shape accuracy requirement for a hull in a spherical shell structure subjected to deep-sea pressure is extremely high. Even [...] Read more.

Spherical shell structures are the most suitable shape for deep-sea pressure hulls because they have ideal mechanical properties for handling symmetrical pressure. However, the shape accuracy requirement for a hull in a spherical shell structure subjected to deep-sea pressure is extremely high. Even minor asymmetry can significantly degrade its mechanical properties. In this study, a new type of spherical deep-sea pressure hull structure and its integral hydro-bulge-forming (IHBF) method are proposed. First, 32 flat metal plate parts are prepared and welded along their straight sides to form a regular polygonally shaped box. Next, water pressure is applied inside the preformed box to create a spherical pressure vessel. We performed a forming experiment using a spherical pressure vessel with a design radius of 250 mm as a verification research object. The radius of the spherical pressure vessel obtained from the forming experiment is 249.32 mm, the error from the design radius is 0.27%, and the roundness of the spherical surface is 2.36 mm. We performed a crushing analysis using uniform external pressure to confirm the crushing and buckling characteristics of the formed spherical pressure vessel. The results show that the work-hardening increased the crushing and buckling load of the spherical pressure vessel, above that of the conventional spherical shell structure. Additionally, it is established that local defects and the size of the weld line significantly and slightly affected the crushing and buckling load of the spherical pressure hull, respectively. Full article

(This article belongs to the Section Mechanical Engineering Design)

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23 pages, 9699 KB

Open AccessEditor’s ChoiceArticle

CFD Investigation of Ventilation Strategies to Remove Contaminants from a Hospital Room

by Mustafa Alkhalaf, Adrian Ilinca and Mohamed Yasser Hayyani

Designs 2023, 7(1), 5; https://doi.org/10.3390/designs7010005 - 4 Jan 2023

Cited by 12 | Viewed by 5400

Abstract

The primary requirement in designing air conditioning systems in healthcare facilities is eliminating contaminants. It is considered one of the crucial health elements in building design, particularly in the presence of many airborne diseases such as COVID-19. The purpose of this numerical research [...] Read more.

The primary requirement in designing air conditioning systems in healthcare facilities is eliminating contaminants. It is considered one of the crucial health elements in building design, particularly in the presence of many airborne diseases such as COVID-19. The purpose of this numerical research is to simulate various ventilation designs for a hospital room model by taking into account results obtained by previous researchers. Four designs with three airflows, 9, 12, and 15 ACH (Air Change per Hour), are applied to explore the capacity of the ventilation system to remove contaminants. The objective is to determine the influence of airflow and the diffuser location distribution on the pollutants elimination represented by carbon dioxide. The Reynold Averaged Navier–Stokes (RANS) equations and the k-ε turbulence model were used as the underlying mathematical model for the airflow. In addition, boundary conditions were extracted from ASHRAE (American Society of Heating, Refrigeration, and Air-Conditioning Engineers Society) ventilation publications and relevant literature. Contrary to what was expected, this study’s results demonstrated that increased ventilation alone does not always improve air distribution or remove more contaminants. In addition, pollutant removal was significantly affected by the outlet’s location. Full article

(This article belongs to the Topic Building Energy and Environment)

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36 pages, 11537 KB

Open AccessEditor’s ChoiceReview

Phase Change Materials—Applications and Systems Designs: A Literature Review

by Bogdan Marian Diaconu, Mihai Cruceru and Lucica Anghelescu

Designs 2022, 6(6), 117; https://doi.org/10.3390/designs6060117 - 18 Nov 2022

Cited by 17 | Viewed by 11654

Abstract

The development of Phase Change Materials (PCMs) applications and products is closely related to the market penetration of the renewable energy technologies. With the initial aim of matching the phase shift between resource availability and demand in solar energy systems, the range of [...] Read more.

The development of Phase Change Materials (PCMs) applications and products is closely related to the market penetration of the renewable energy technologies. With the initial aim of matching the phase shift between resource availability and demand in solar energy systems, the range of PCM applications expanded rapidly during the last decades, entering economic sectors where some form of passive thermal regulation was required. This review focuses on examining both conventional applications and recent advances and niche areas—such as space applications—where PCM-based systems demonstrated a potential to improve the operation at process level. The literature survey conducted here gave special attention to recent application of PCM-based systems such as data centres cooling and electric vehicles battery thermal management. Recent advances in PCM-based systems designs were surveyed in the second part of the article. The main PCM containment and system integration directions were discussed and recent representative studies were discussed. Some topics considered marginal but nevertheless essential to large scale implementation of PCM-based systems were mentioned and their coverage in the literature was assessed: health risks, environmental and lifecycle issues. Full article

(This article belongs to the Section Mechanical Engineering Design)

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26 pages, 10284 KB

Open AccessEditor’s ChoiceArticle

Design of an Integrated, Six-Phase, Interleaved, Synchronous DC/DC Boost Converter on a Fuel-Cell-Powered Sport Catamaran

by Michael Rimondi, Riccardo Mandrioli, Vincenzo Cirimele, Lohith Kumar Pittala, Mattia Ricco and Gabriele Grandi

Designs 2022, 6(6), 113; https://doi.org/10.3390/designs6060113 - 14 Nov 2022

Cited by 6 | Viewed by 3814

Abstract

This paper describes the preliminary analysis, design and implementation phases of a DC/DC boost converter dedicated to the Futura catamaran propulsion chain developed by the UniBoAT team at the University of Bologna. The main goal of the project was the reduction of the [...] Read more.

This paper describes the preliminary analysis, design and implementation phases of a DC/DC boost converter dedicated to the Futura catamaran propulsion chain developed by the UniBoAT team at the University of Bologna. The main goal of the project was the reduction of the converter’s weight by eliminating the use of heat sinks and by reducing the component size, especially inductors and capacitors. The obtained converter is directly integrated into the structure containing the fuel-cell stack. The realized converter was based on an interleaved architecture with six phases controlled through the average current mode control. The design was validated through simulations carried out using the LT-Spice software, whereas experimental validations were performed by means of both bench tests and on-field tests. Detailed thermal and efficiency analyses were provided with the bench tests under the two synchronous and non-synchronous operating modes and with the adoption of the phase-shedding technique. Prototype implementation and performance in real operating conditions are discussed in relation to on-field tests. The designed converter can be used in other applications requiring a voltage-controlled boost converter. Full article

(This article belongs to the Topic Advanced Electrical Machines and Drives Technologies)

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21 pages, 1249 KB

Open AccessEditor’s ChoiceArticle

Study of Energy Loss for Distributed Power-Flow Assignment in a Smart Home Environment

by Ruengwit Khwanrit, Yuto Lim, Saher Javaid, Somsak Kittipiyakul and Yasuo Tan

Designs 2022, 6(6), 99; https://doi.org/10.3390/designs6060099 - 24 Oct 2022

Cited by 8 | Viewed by 2396

Abstract

Today, renewable energy resources are a critical component of distributed energy systems. However, their intermittent nature makes them unstable energy sources, making them very difficult to use optimally in any energy system. Battery storage is a viable solution for this issue. In this [...] Read more.

Today, renewable energy resources are a critical component of distributed energy systems. However, their intermittent nature makes them unstable energy sources, making them very difficult to use optimally in any energy system. Battery storage is a viable solution for this issue. In this paper, we consider distributed power-flow assignment consisting of unstable power generators, unpredictable power loads, and multiple energy storage systems (ESSs), with different combinations of logical power connections between them. We propose power-flow assignment (PFA) algorithms to deal with single and multiple loads to address the possibility of reducing energy loss and improving distributed power-flow assignment with the presence of ESSs in a smart home environment. Simulation results reveal that the increment of logical power connections between generators, loads, and storage systems can significantly reduce energy loss. The proposed PFA algorithms can reduce energy loss by about 67% compared to a power-flow assignment for which all the generated power is stored in an ESS directly during winter. The results further show that spring has the highest energy loss and stored energy in ESS compared to other seasons. Full article

(This article belongs to the Special Issue Smart Home Design)

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25 pages, 2707 KB

Open AccessEditor’s ChoiceArticle

Adaptive Control of Energy Storage Systems for Real-Time Power Mediation Based on Energy on Demand System

by Saher Javaid and Takekazu Kato

Designs 2022, 6(5), 97; https://doi.org/10.3390/designs6050097 - 19 Oct 2022

Cited by 3 | Viewed by 2233

Abstract

The concept of i-Energy as a new smart demand-side energy management system is proposed, which can realize the versatile and efficient control of e-power flows between distributed generators, numerous appliances, and energy storage systems in the home domain, factories, offices, and local communities. [...] Read more.

The concept of i-Energy as a new smart demand-side energy management system is proposed, which can realize the versatile and efficient control of e-power flows between distributed generators, numerous appliances, and energy storage systems in the home domain, factories, offices, and local communities. The Energy on Demand (EoD) system is proposed, which is the automatic power control and management system that supplies power to home appliances based on the power demand requests issued from the home appliances. The EoD system can guarantee the reduction in total power consumption by implementing a ceiling control while keeping the quality of life (QoL) of the home user considering the limitation of power supply. This paper proposes an adaptive battery storage management and control method based on the EoD system, which we call the “storage-supported EoD system”. In particular, the storage-supported EoD system can handle multiple power generators, including storage batteries. The overall goals of this paper are not limited to the extension of multiple power supplies only; rather, it provides additional contributions, which are (i) extend the existing power consumption control of home appliances and peak demand shift control (i.e., EoD system) by adding a second power source, i.e., a storage battery system; (ii) propose adaptive storage system design and management for the EoD system; (iii) realize minimum storage capacity for large peak power consumption; and (iv) minimize the home user’s discomfort level due to the limited power supply of one power source. The simulation results have shown the effectiveness of the proposed algorithm with a couple of experiments using real-life data in the smart apartment room. Additionally, simulation results are presented to compare and evaluate the proposed system performance with the EoD system. Full article

(This article belongs to the Section Energy System Design)

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25 pages, 5020 KB

Open AccessEditor’s ChoiceArticle

Preliminary Sizing of Electric-Propulsion Powertrains for Concept Aircraft Designs

by Josin Hu and Julian Booker

Designs 2022, 6(5), 94; https://doi.org/10.3390/designs6050094 - 13 Oct 2022

Cited by 7 | Viewed by 4639

Abstract

The drive towards a greener and more sustainable future is encouraging the aviation industry to move towards increasing electrification of its fleet. The development of electric propulsion technologies also requires new approaches to assess their viability in novel configurations. A methodology is proposed [...] Read more.

The drive towards a greener and more sustainable future is encouraging the aviation industry to move towards increasing electrification of its fleet. The development of electric propulsion technologies also requires new approaches to assess their viability in novel configurations. A methodology is proposed which consists of four sub-procedures; powertrain modelling, performance analysis, aerodynamic modelling, and sizing. This approach initially considers powertrain modelling using AIAA symbol representations, and a review of the available literature establishes state-of-the-art component values of efficiency, specific power, specific energy, and specific fuel consumption. The sizing procedure includes a mission and aerodynamic analysis to determine the energy and power requirements, and it relies on a mass regression model based on full-electric, hybrid, VTOL and fixed-wing aircraft found in the literature. The methodology has been applied to five case studies which are representative of a wide range of missions and configurations. Their predicted masses from the sizing procedure have been validated against their actual masses. The predicted total mass shows generally good agreement with the actual values, and in addition, accurate values for active mass have been predicted. A sensitivity analysis of the sizing procedure suggests that future work may include a more accurate analysis of aerodynamics and mission if the methodology were to be applied for selecting aircraft concepts. Full article

(This article belongs to the Topic Advanced Electric Vehicle Technology)

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19 pages, 5122 KB

Open AccessFeature PaperEditor’s ChoiceArticle

Design of a Hybrid Electric Power-Split Transmission for Braking Energy Recovery in a Drilling Rig

by Antonella Castellano, Daniele Leone and Marco Cammalleri

Designs 2022, 6(5), 74; https://doi.org/10.3390/designs6050074 - 28 Aug 2022

Cited by 5 | Viewed by 3089

Abstract

Despite the promising potential of the hybrid electric power-split layout, its broader market penetration is prevented by the large number of feasible solutions and the constructive complexity, which overcomplicate the design process. Moreover, due to the lack of relevant literature references, the power-split [...] Read more.

Despite the promising potential of the hybrid electric power-split layout, its broader market penetration is prevented by the large number of feasible solutions and the constructive complexity, which overcomplicate the design process. Moreover, due to the lack of relevant literature references, the power-split transmissions design is even more difficult if concerning applications outside the automotive and agricultural sectors. In this paper, a general parametric model already available in the literature to design a single-mode power-split transmission with up to two planetary gear sets and six ordinary gear sets was applied to hybridize an oil drilling rig to recover energy braking during the gravity-driven lowering phases. This is the first power-split electric hybridization of a drilling rig. Two solutions differing in engine power size are presented. Thanks to the modularity of the model, the procedure enabled the optimization of the ICE, the electric machines, and the gear sets through decoupled design phases. Full article

(This article belongs to the Section Mechanical Engineering Design)

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20 pages, 5394 KB

Open AccessEditor’s ChoiceArticle

A Predesign Methodology for Power Electronics Based on Optimization and Continuous Models: Application to an Interleaved Buck Converter

by Mylène Delhommais, Timothé Delaforge, Jean-Luc Schanen, Frédéric Wurtz and Cécile Rigaud

Designs 2022, 6(4), 68; https://doi.org/10.3390/designs6040068 - 3 Aug 2022

Cited by 2 | Viewed by 2385

Abstract

This paper proposes an approach dedicated to power electronics preliminary design. It consists in setting the optimization problem in an “imaginary” world by considering all decision variables to be continuous. The method is illustrated in detail with the real case study of an [...] Read more.

This paper proposes an approach dedicated to power electronics preliminary design. It consists in setting the optimization problem in an “imaginary” world by considering all decision variables to be continuous. The method is illustrated in detail with the real case study of an Interleaved Buck Converter. The models used are briefly described, and the focus is also placed on all possible applications of such a quick design methodology: considering several operating points, checking various candidate technologies and negotiating the specifications of the converter with the partners. Full article

(This article belongs to the Section Energy System Design)

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17 pages, 12399 KB

Open AccessEditor’s ChoicePerspective

A Classification of Aperiodic Architected Cellular Materials

by Irving E. Ramirez-Chavez, Daniel Anderson, Raghav Sharma, Christine Lee and Dhruv Bhate

Designs 2022, 6(4), 63; https://doi.org/10.3390/designs6040063 - 7 Jul 2022

Cited by 13 | Viewed by 3526

Abstract

Architected cellular materials encompass a wide range of design and performance possibilities. While there has been significant interest in periodic cellular materials, recent emphasis has included consideration of aperiodicity, most commonly in studies of stochastic and graded cellular materials. This study proposes a [...] Read more.

Architected cellular materials encompass a wide range of design and performance possibilities. While there has been significant interest in periodic cellular materials, recent emphasis has included consideration of aperiodicity, most commonly in studies of stochastic and graded cellular materials. This study proposes a classification scheme for aperiodic cellular materials, by first dividing the design domain into three main types: gradation, perturbation, and hybridization. For each of these types, two design decisions are identified: (i) the feature that is to be modified and (ii) the method of its modification. Considerations such as combining different types of aperiodic design methods, and modulating the degree of aperiodicity are also discussed, along with a review of the literature that places each aperiodic design within the classification developed here, as well as summarizing the performance benefits attributed to aperiodic cellular materials over their periodic counterparts. Full article

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29 pages, 2521 KB

Open AccessFeature PaperEditor’s ChoiceArticle

Secured Multi-Dimensional Robust Optimization Model for Remotely Piloted Aircraft System (RPAS) Delivery Network Based on the SORA Standard

by Armin Mahmoodi, Leila Hashemi, Jeremy Laliberté and Richard C. Millar

Designs 2022, 6(3), 55; https://doi.org/10.3390/designs6030055 - 15 Jun 2022

Cited by 17 | Viewed by 3610

Abstract

The range of applications of RPAs in various industries indicates that their increased usage could reduce operational costs and time. Remotely piloted aircraft systems (RPASs) can be deployed quickly and effectively in numerous distribution systems and even during a crisis by eliminating existing [...] Read more.

The range of applications of RPAs in various industries indicates that their increased usage could reduce operational costs and time. Remotely piloted aircraft systems (RPASs) can be deployed quickly and effectively in numerous distribution systems and even during a crisis by eliminating existing problems in ground transport due to their structure and flexibility. Moreover, they can also be useful in data collection in damaged areas by correctly defining the condition of flight trajectories. Hence, defining a framework and model for better regulation and management of RPAS-based systems appears necessary; a model that could accurately predict what will happen in practice through the real simulation of the circumstances of distribution systems. Therefore, this study attempts to propose a multi-objective location-routing optimization model by specifying time window constraints, simultaneous pick-up and delivery demands, and the possibility of recharging the used batteries to reduce, firstly, transport costs, secondly, delivery times, and thirdly, estimated risks. Furthermore, the delivery time of the model has been optimized to increase its accuracy based on the uncertain conditions of possible traffic scenarios. It is also imperative to note that the assessment of risk indicators was conducted based on the Specific Operations Risk Assessment (SORA) standard to define the third objective function, which was conducted in a few previous studies. Finally, it shows how the developed NSGA-II algorithm in this study performed successfully and reduced the objective function by 31%. Comparing the obtained results using an NSGA-II meta-heuristic approach, through the rigorous method GAMS, indicates that the results are valid and reliable. Full article

(This article belongs to the Special Issue Unmanned Aerial System (UAS) Modeling, Simulation and Control)

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24 pages, 15109 KB

Open AccessEditor’s ChoiceReview

Advanced Thermal Management Systems for High-Power Lithium-Ion Capacitors: A Comprehensive Review

by Danial Karimi, Hamidreza Behi, Joeri Van Mierlo and Maitane Berecibar

Designs 2022, 6(3), 53; https://doi.org/10.3390/designs6030053 - 9 Jun 2022

Cited by 8 | Viewed by 4459

Abstract

The acceleration demand from the driver in electric vehicles (EVs) should be supported by high-power energy storage systems (ESSs). In order to satisfy the driver’s request, the employed ESS should have high power densities. On the other hand, high energy densities are required [...] Read more.

The acceleration demand from the driver in electric vehicles (EVs) should be supported by high-power energy storage systems (ESSs). In order to satisfy the driver’s request, the employed ESS should have high power densities. On the other hand, high energy densities are required at the same time for EVs’ traction to minimize the range anxiety. In this context, a novel ESS has emerged that can provide high power and energy densities at the same time. Such technology is called lithium-ion capacitor (LiC), which employs Li-doped carbon as negative electrode and activated carbon as positive electrode. However, high heat generation in high current applications is an issue that should be managed to extend the LiCs life span. Hence, a proper thermal management system (TMS) is mandatory for such a hybrid technology. Since this ESS is novel, there are only several TMSs addressed for LiCs. In this review article, a literature study regarding the developed TMSs for LiCs is presented. Since LiCs use Li-doped carbon in their negative electrodes, lithium-titanate oxide (LTO) batteries are the most similar lithium-ion batteries (LiBs) to LiCs. Therefore, the proposed TMSs for lithium-ion batteries, especially LTO batteries, have been explained as well. The investigated TMSs are active, passive, and hybrid cooling methods The proposed TMSs have been classified in three different sections, including active methods, passive methods, and hybrid methods. Full article

(This article belongs to the Special Issue Battery System Design)

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14 pages, 8509 KB

Open AccessEditor’s ChoiceArticle

An SIC-Fed Low-Profile Wideband Metamaterial-Based Antenna Array for 5G Wireless Cellular Networks

by Shengjie Wang, Liguo Sun and Jean de Dieu Ntawangaheza

Designs 2022, 6(3), 43; https://doi.org/10.3390/designs6030043 - 9 May 2022

Viewed by 2784

Abstract

In this paper, we propose a metamaterial (MTM)-based low-profile wideband antenna and its array using a substrate integrated cavity (SIC) feed structure for 5G wireless cellular networks. The proposed wideband antenna consists of two sets of square mushroom-like arrays; a semi-ground plane and [...] Read more.

In this paper, we propose a metamaterial (MTM)-based low-profile wideband antenna and its array using a substrate integrated cavity (SIC) feed structure for 5G wireless cellular networks. The proposed wideband antenna consists of two sets of square mushroom-like arrays; a semi-ground plane and a microstrip line-fed bow-tie radiator. Due to the unique in-phase reflection characteristic of the mushroom-like metamaterial, the bow-tie antenna wideband performance is maintained while the distance between the bow-tie radiator and the metamaterial-based semi-ground is considerably reduced to 0.014λ₀ (λ₀ is the operating wavelength at 5 GHz in free space), thereby satisfying the compact size requirement desirable in many wireless communication systems. The in-phase reflection of the mushroom unit cell is applied to analyze and explain the wideband performance of the presented antenna. The proposed dielectric-filled (

ε_{r} = 3.55

) MTM-based wideband antenna element has an overall size of 1.0λ₀ × 0.8λ₀ × 0.054λ₀ and attains a measured (

| S_{11} | < - 10 dB

) bandwidth of 31.3%. Subsequently, an SIC feed structure is employed to form an array antenna, and a measured (

| S_{11} | < - 10 dB

) bandwidth of about 17% is obtained. Across the operating bandwidth, which partly covers the 5G wireless communication in the sub-6 GHz band and 5-GHz WLAN, the antenna array achieved an average gain of 6.6 dBi and a radiation efficiency greater than 73%. Full article

(This article belongs to the Section Electrical Engineering Design)

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32 pages, 14632 KB

Open AccessEditor’s ChoiceArticle

Impacts of Location on Designs and Economics of DIY Low-Cost Fixed-Tilt Open Source Wood Solar Photovoltaic Racking

by Nicholas Vandewetering, Koami Soulemane Hayibo and Joshua M. Pearce

Designs 2022, 6(3), 41; https://doi.org/10.3390/designs6030041 - 21 Apr 2022

Cited by 19 | Viewed by 6661

Abstract

Although small solar photovoltaic (PV) systems avoid most soft costs, they still have a relatively high $/W value due to racking costs. In order to fulfill the promise of small-scale plug-and-play solar, a do-it-yourself PV rack design is provided and analyzed here for [...] Read more.

Although small solar photovoltaic (PV) systems avoid most soft costs, they still have a relatively high $/W value due to racking costs. In order to fulfill the promise of small-scale plug-and-play solar, a do-it-yourself PV rack design is provided and analyzed here for six criteria: (1) made from locally-accessible renewable materials, (2) 25-year lifetime to match PV warranties, (3) able to be fabricated by average consumers, (4) able to meet Canadian structural building codes, (5) low cost and (6) that it is shared using an open-source license. The open-source wood-based fixed-tilt ground-mounted bifacial photovoltaic rack design evaluated here was found to be appropriate throughout North America. Economic analysis of the bill of materials showed the racking system ranges from 49% to 77% less expensive compared to commercial proprietary racking in Canada. The racking design, however, is highly dependent on the cost of lumber that varies widely throughout the world. Even for an absolute lower-cost design in Togo due to a lower fixed tilt angle and lower loads from lack of snow, it was not found to be economic because of the relatively high cost of wood. The recent volatile lumber market warrants local evaluation from those considering the use of the open-source design. This design, however, provides for a PV rack that can be manufactured with distributed means throughout most of the world enabling more equitable access to solar energy to support a circular bioeconomy. Full article

(This article belongs to the Topic Building Energy and Environment)

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