Search Results (164)

This study investigates the integration of eco-design strategies in the energy renovation of mid-20th century heritage buildings, using the Antonio Rueda Residential Complex in Valencia (Spain) as a representative case study. The research addresses the reconciliation between heritage conservation and contemporary environmental objectives by evaluating the building in terms of its construction and current performance. The multidisciplinary working methodology consists of creating a BIM-based workflow (Revit + Autodesk Insight) to generate an analytical energy model, quantify Operational Carbon, and evaluate the impact of lighting inside the homes to simulate the impacts of the intervention strategies. This is justified as existing buildings are energy intensive and heavily dependent on fossil fuels, largely due to insufficient façade insulation, obsolete window systems, and limited solar protection. Nine refurbishment scenarios were developed, ranging from reversible improvements to the building envelope to volumetric extensions inspired by the principles of eco-design and circularity. Comparative simulations suggest that specific improvements could significantly reduce energy demand while remaining compatible with the architectural identity of the complex. Full article

This paper reviews key parameters which may cause unacceptable water hammer loads in Francis-turbine hydropower schemes. Water hammer control strategies are presented for this context including operational scenarios (closing and opening laws), surge control devices, redesign of the pipeline components, or limitation of operating conditions. Theoretical water hammer models and solutions are outlined and discussed. Case studies include simple and complex new and refurbished hydropower systems including headrace and tailrace tunnels, surge tanks of various designs, and different penstock layouts. The case studies in this paper cover the application of both commercial and in-house software packages for hydraulic transient analysis. Two-stage guide vane closing law, increased unit inertia and surge tank(s) are used in the cases considered to keep the water hammer within the prescribed limits. Typical values for the maximum pressure head at the turbine inlet and the maximum unit speed rise during normal transient regimes were in the range of 10 to 35% of the maximum gross head and 35 to 50% above the nominal speed, respectively. The agreement between computational results using both software packages, and field test results is well within the limits of ±5% accepted in hydropower engineering practice. Full article

The lack of detailed design information in legacy hydropower plants creates challenges for modernising their ageing turbine components. This research advances a digitalisation approach which combines inverse design methodology (IDM) with multi-objective genetic algorithms (MOGA) and computational fluid dynamics (CFD) to digitally reconstruct and optimise the Bérchules Francis turbine runner and guide vane geometries using limited available legacy data, avoiding invasive techniques. A two-stage optimisation process was conducted. The first stage of runner blade optimisation achieved a 22.7% reduction in profile loss and a 16.8% decrease in secondary flow factor while raising minimum pressure from −877,325.5 Pa to −132,703.4 Pa. Guide vane optimisation during Stage 2 produced additional performance gains through a 9.3% reduction in profile loss and a 20% decrease in secondary flow factor and a minimum pressure increase to +247,452.1 Pa which represented an 183% improvement. The CFD validation results showed that the final turbine efficiency reached 93.7% while producing more power than the plant’s rated 942 kW. The sensitivity analysis revealed that leading edge loading at mid-span and normal chord proved to be the most significant design parameters affecting pressure loss and flow behaviour metrics. The research proves that legacy turbines can be digitally restored through hybrid optimisation and CFD workflows, which enables data-driven refurbishment design without needing complete component replacement. Full article

Modern research laboratories are constantly evolving to meet the growing demands for precision, quality, and flexibility in scientific work. The modernization of existing experimental test benches plays a crucial role in improving efficiency, optimizing processes, and ensuring operational safety. This requires updates to their design, experimental methods, data collection, and results recording—all of which provide the foundation for developing new research concepts. An increasing number of innovations are now guided by the principle of minimizing environmental impact. In line with this approach, an innovative modernization of a tube furnace research station was carried out, based on the concepts of sustainable development and the zero-waste philosophy. To enable thermogravimetric analyses of coffee waste, a previously incomplete tube furnace was refurbished using recycled components. The primary objective was to expand the research capabilities of the existing workstation. As part of the modernization, three indicators of reuse efficiency were calculated: the quantitative indicator W_re-use, the mass indicator $W_{re\text{-}use}^{mass}$, and the cost indicator $W_{re\text{-}use}^{value}$. A quantitative index of 78% and a mass index of approximately 76% were achieved, while the economic value of the recovered components accounted for 11% of the total value of the revitalized research station. This strategy significantly reduced waste generation, carbon dioxide emissions, and the consumption of primary raw materials. Full article

This research investigates the integration of green cores as central biophilic elements in residential architecture, proposing a climate-responsive design methodology grounded in architectural optimization. The study begins with the full-scale refurbishment of a compact urban apartment, wherein interior partitions, fenestration and material systems were reconfigured to embed vegetated zones within the architectural core. Light exposure, ventilation potential and spatial coherence were maximized through data-driven design strategies and structural modifications. Integrated planting modules equipped with PAR-specific LED systems ensure sustained vegetation growth, while embedded environmental infrastructure supports automated irrigation and continuous microclimate monitoring. This plant-centered spatial model is evaluated using quantifiable performance metrics, establishing a replicable framework for optimized indoor ecosystems. Photosynthetically active radiation (PAR)-specific LED systems and embedded environmental infrastructure were incorporated to maintain vegetation viability and enable microclimate regulation. A programmable irrigation system linked to environmental sensors allows automated resource management, ensuring efficient plant sustenance. The configuration is assessed using measurable indicators such as daylight factor, solar exposure, passive thermal behavior and similar elements. Additionally, a post-occupancy expert assessment was conducted with several architects evaluating different aspects confirming the architectural and spatial improvements achieved through the refurbishment. This study not only demonstrates a viable architectural prototype but also opens future avenues for the development of metabolically active buildings, integration with decentralized energy and water systems, and the computational optimization of living infrastructure across varying climatic zones. Full article

The utilization of knowledge management (KM) assists construction companies in planning for waste management. This study applies KM in the material recovery of a public sector building renovation, focusing on aluminum composite panels (ACPs). The cost/benefit analysis (CBA) method examines suitable scenarios, where costs and benefits cover economic, environmental, and social perspectives. The cost/benefit (C/B) ratios reveal that the repurposing scenario, where ACP waste is repurposed as signboards, is the most suitable scenario, with a C/B of 0.96. The refurbishing scenario, in which ACP waste is refurbished as new facades, may be considered if the labor cost could be reduced through training. The repurposing scenario is further examined with a sensitivity analysis and the Leadership in Energy and Environmental Design certification, and it is found that implementing this scenario serves as a beginning step toward green certification and aligns with Thailand’s national strategies for green building promotion and the long-term Net Zero 2065 target. The study results serve as a guideline for Thailand’s transition toward a low-carbon and resource-efficient construction sector. Future studies are recommended to examine the complex relationships between costs and benefits and to track dynamic changes in the C/B ratio over time. Full article

The construction of buildings using shipping containers (SCs) is a way to extend their useful life. They are constructed by modifying the structure, thermal, and acoustic conditioning by improving the envelope and creating openings for lighting and ventilation purposes. This study explores the architectural adaptation of SCs to sustainable residential housing, focusing on structural, thermal, and acoustic performance. The project centers on a case study in Madrid, Spain, transforming four containers into a semi-detached, multilevel dwelling. The design emphasizes modular coordination, spatial flexibility, and structural reinforcement. The retrofit process includes the integration of thermal insulation systems in the ventilated façades and sandwich roof panels to counteract steel’s high thermal conductivity, enhancing energy efficiency. The acoustic performance of the container-based dwelling was assessed through in situ measurements of façade airborne sound insulation and floor impact noisedemonstrating compliance with building code requirements by means of laminated glazing, sealed joints, and floating floors. This represents a novel contribution, given the scarcity of experimental acoustic data for residential buildings made from shipping containers. Results confirm that despite the structure’s low surface mass, appropriate design strategies can achieve the required sound insulation levels, supporting the viability of this lightweight modular construction system. Structural calculations verify the building’s load-bearing capacity post-modification. Overall, the findings support container architecture as a viable and eco-efficient alternative to conventional construction, while highlighting critical design considerations such as thermal performance, sound attenuation, and load redistribution. The results offer valuable data for designers working with container-based systems and contribute to a strategic methodology for the sustainable refurbishment of modular housing. Full article

Sustainable product development demands components that last longer, consume less energy, and can be refurbished within circular supply chains. This study introduces a digital replica-based predictive prototyping workflow for industrial crusher blades that meets these goals. Six commercially used blade geometries (A–F) were recreated as high-fidelity finite-element models and subjected to an identical 5 kN cutting load. Comparative simulations revealed that a triple-edged hooked profile (Blade A) reduced peak von Mises stress by 53% and total deformation by 71% compared with a conventional flat blade, indicating lower drive-motor power and slower wear. To enable fast virtual prototyping and condition-based maintenance, deformation was subsequently predicted using a data-efficient machine-learning model. Multi-view image augmentation enlarged the experimental dataset from 6 to 60 samples, and an XGBoost regressor, trained on computer-vision geometry features and engineering parameters, achieved R² = 0.996 and MAE = 0.005 mm in five-fold cross-validation. Feature-importance analysis highlighted applied stress, safety factor, and edge design as the dominant predictors. The integrated method reduces development cycles, reduces material loss via iteration, extends the life of blades, and facilitates refurbishment decisions, providing a foundation for future integration into digital twin systems to support sustainable product development and predictive maintenance in heavy-duty manufacturing. Full article

To address incomplete die filling, high cracking tendency, and severe die wear in the conventional forging of AISI-410 martensitic stainless steel U-shaped forgings, an optimized billet volume pre-allocation strategy was proposed. Two improved forging schemes for the U-shaped forgings were designed: the Arc Concave Flattening Scheme (adding arc-shaped concave features to the flattening die for corner volume compensation) and Preformed Volume Allocation Scheme (incorporating a preforming step for strategic volume pre-allocation at ends and corners). Finite Element Analysis employing the Oyane damage model and Archard wear model was employed to simulate and optimize the forging process. The optimal scheme was applied to production trials. The results demonstrated that the Preformed Volume Allocation Scheme significantly improved the geometric compatibility between the billets and the final forging die cavity. As a result, the billet’s temperature, strain, and equivalent stress uniformity increased, reducing cracking tendency. Moreover, the rise in the mitigated temperature and stress concentration resulted in reduced final forging die wear. Production trials confirmed a qualified rate of ~96% (34% higher than the Original Scheme). The final forging die service life reached 300 pieces per refurbishment cycle, showing a 50% improvement. This work provides theoretical and practical guidance for optimizing the forging processes of complex martensitic stainless steel components. Full article

Durable plastics are a sustainability challenge for healthcare products. Orthopedic products are regulated with strict specifications for human tissue interactions. Healthcare engineers and managers select plastic to meet the full range of material properties. Plastic is plentiful, low cost, and reliable, with established supply chains. Used plastic products can be discarded using existing waste management systems with low externality costs for orthopedic businesses. However, plastic is produced from fossil petroleum, raising issues for sustainability commitments of healthcare product companies. Barriers to the transition away from single-use plastic toward circular systems and bio-based healthcare products have been studied, but the transition is a goal that has yet to be realized. This research article reports on a transition engineering design sprint with a medium-sized orthopedic company specializing in orthoses for children and teenagers. The design sprint process engages company experts with systems perspectives on the role of unsustainable plastic in orthopedic healthcare and illuminates opportunities for capturing value in business transition. Two system transition project concepts were co-developed. The first concept is a plastics value map that aims to converge the satisfaction of essential needs with the usefulness of plastics under the limitations of a biophysically constrained future economy. The second concept is an orthopedics library data system concept that would allow reusing of fit-for-purpose used products and to inform the refurbishment of used products. In addition to an explanation of the design of the two concepts, the article presents reflections of co-design stakeholders on the usefulness and usability of the concepts. The article provides a real-world application of the co-design processes in transition engineering and the reflection by the company on the value of the results. The results indicate that the co-designed concepts could enable the company to address its sustainability aspirations and potentially resolve the dissonance of sustainability and business viability. Full article

The renovation of buildings impacts various factors; one of them is the economic aspect, which has a significant influence on the decision-making process in building refurbishment, especially in social housing. An often-neglected aspect of renovation is the influence of climate change. Typically, historical climate data are used to estimate the building’s future energy needs. However, due to climate change, this approach may fail to accurately represent future environmental conditions, resulting in miscalculations in energy consumption and costs. This study analyzed a building archetype obtained from the TABULA webtool with the characteristics of a social house building located in Trieste. Dynamic simulations were performed using DesignBuilder and EnergyPlus software and future climate models (the GERICS_CNRM-CM5 and GERICS_IPSL-CM5A-MR models obtained from the EURO-CORDEX database). The projected energy needs of the renovated building and its economic effects were compared with current scenarios, and due to the uncertainties in economic parameters, the outcome is expressed in terms of percentiles of the Net Present Value (NPV). The results of this study show that since temperature increases in the future, the need for energy in the heating period reduces, while the need for cooling increases, directly affecting the statistical distribution of the NPV. Full article

Cables are critical to the safe and reliable operation of nuclear power plants (NPPs) since they are widely used as a connection medium for various safety-critical equipment. According to research data and operational experience (OPEX), cable materials can degrade with time, resulting in reduced dielectric strength and higher leakage current. Cables may degrade gradually over time under normal service conditions and fail unexpectedly as a result of sudden exposure to harsher environments, such as Secondary Steam Line Breaks (SSLBs), or when required to operate under the severe conditions of a design basis event, such as a Loss-of-Coolant Accident (LOCA). To assess the condition of medium- and low-voltage cables in Canadian nuclear power plants, numerous inspection methods and electrical testing techniques are employed. These techniques include dielectric spectroscopy, polarization/depolarization current analysis, reflectometry, dielectric standby tests, AC partial discharge, and very-low-frequency (VLF) Tan Delta assessments for medium-voltage (MV) cables. While these methods provide precise diagnostic insights, they require cables to be disconnected at both ends and de-energized, posing operational constraints. Consequently, on-line plant cable monitoring has garnered significant interest, particularly for new reactor developments and large-scale NPP refurbishments. This paper provides a comprehensive benchmarking of existing technologies and a state-of-the-art review of modern cable assessment methodologies. It examines commercially available solutions and ongoing research in power testing for low-voltage (LV) and MV cables, with a particular focus on their applicability in nuclear power settings. Full article

In the case of load increases and the refurbishment of existing buildings, it is often necessary to carry out strengthening measures on existing timber beams. When timber concrete composite (TCC) ceilings cannot be used, it is possible to reinforce the undersides of the beams with structural steel or fiber composites (aramid or carbon-fiber-reinforced polymer). This work investigates how significant effects on the load-bearing and deformation behavior can be achieved with these materials in terms of construction practice. The article is intended to show structural engineers which reinforcement measures lead to which forces, deformations, etc., and how these are utilized. This should form the basis for the planning of reinforcement measures, as it is not clear from the beginning whether AFRP, CFRP, or steel is the most suitable material. For this purpose, a comparative parameter study was carried out under practical conditions and with a variable degree of reinforcement using the corresponding formulas. The internal forces in the timber and reinforcement cross-sections, the deflection behavior, and the failure loads at the strength and design levels were calculated. It was demonstrated that, particularly for steel and carbon-fiber-reinforced polymer (CFRP) reinforcements, significant increases in the ultimate load can be achieved and the often-important deformation behavior can be significantly improved. Especially the steel variant leads to high improvements in deflection and breaking load behavior, with the base material (wood) also being utilized more economically as a result. A comparative ecological study in the form of the global warming potential showed that reinforcement methods are also advantageous from the point of view of sustainability compared to renovations with timber concrete composite slabs or new concrete slabs. Full article

Background: Optimizing reverse chains is more difficult than forward linear supply chains. Careful consideration should be given to recovery strategies to optimize product reuse as well as recycling. Methods: Using a 450-product dataset from the Melbourne area collection project and literature sources, we applied a calculation model with four recovery options. It modeled different return quality levels, three market segments, cost structures, buy-back and resell prices, carbon emissions, and the percentage of reuse and recycling for the four Rs (volume-based). We compared fifteen recovery strategies with one, two, three, or four recovery options and carried out sensitivity analyses to explore the impact of return volumes and quality, recovery cost, and market prices. Results: The main findings are as follows: (i) Product reuse has a lot of potential, but currently only for premium brands and requires the returned products to be of good quality. (ii) Environmental footprints are reduced in almost all scenarios, so economic viability is the main bottleneck in applying (more) reuse. (iii) Eco-design and circular business models may pave the way to reduce costs and increase market acceptance. Conclusions: We conclude with three suggested strategies for promoting reuse of electronic equipment: 1. Collecting discarded products earlier; 2. Incentivizing modular product design; 3. Greater consistency in asset management and refurbishment operations. Full article

The construction sector plays a pivotal role in urban development, providing a critical opportunity to foster a cultural shift towards the regeneration of housing stock. This shift focuses on sustainable and resilient urban interventions to extend the lifespan of buildings, starting from the design phase. In this context, the European Union’s Level(s) framework, which establishes sustainability indicators, is particularly relevant to this research, as it promotes circular economy principles and building resilience. The framework provides a comprehensive set of indicators that guide resilient housing rehabilitation methodologies. Indicator 2.3 supports the design and renovation of obsolete housing, emphasizing the maximization of resilience against climatic, functional, and socio-economic impacts. Meanwhile, Indicator 4.2 evaluates the thermal comfort of building occupants concerning indoor conditions throughout the year. The primary aim of this study is to develop a resilient housing rehabilitation methodology based on Level(s), which includes (i) assessing the current resilience of a pilot case, (ii) designing new resilient housing configurations, (iii) evaluating thermal comfort duration for older adults, and (iv) analyzing cost amortization. The research findings indicate that the proposed rehabilitation approach significantly improves occupants’ resilience to climate-related stressors and thermal comfort, particularly vulnerable populations such as older adults. Additionally, the study highlights the importance of adapting thermal comfort standards for these populations and demonstrates the cost-effectiveness of resilience strategies. The outcomes contribute to a flexible and accessible refurbishment model that meets diverse tenant needs, offering a scalable solution for sustainable urban interventions. Full article