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Heat Transfer in Energy Conversion Systems

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "I: Energy Fundamentals and Conversion".

Deadline for manuscript submissions: closed (31 October 2020) | Viewed by 33796

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Special Issue Editors


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Guest Editor
Dipartimento di Ingegneria, Università degli Studi di Napoli “Parthenope”, Centro Direzionale, Isola C4, 80143 Napoli, Italy
Interests: energy systems; energy efficiency; geothermal energy; numerical modeling; heat transfer
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Dipartimento di Ingegneria, Università degli Studi di Napoli “Parthenope”, Centro Direzionale, Isola C4, 80143 Napoli, Italy
Interests: heat and mass transport in porous media and free fluids; finite elements; innovative energy conversion systems; renewable energy sources; geothermal energy; fuel cells; heat and mass transfer in biomedical applications; waste to energy systems
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Dipartimento di Ingegneria, Università degli Studi di Napoli “Parthenope”, Centro Direzionale, Isola C4, 80143 Napoli, Italy
Interests: thermodynamic and thermo-economic analysis of advanced energy systems; energy saving; renewable energy sources; dynamic modeling of energy conversion systems; innovative energy conversion systems; energy planning; thermo-fluid-dynamic measurements

Special Issue Information

Dear Colleagues,

The purpose of This Special Issue is to collect interesting and original studies demonstrating the importance of properly taking into account heat transfer phenomena in modern energy conversion systems, in order to improve the conversion efficiency, design and operation techniques of these systems.

Given the importance of verification and validation issues for numerical codes, contributions dealing with both numerical approaches and combined numerical-experimental approaches are appreciated and invited in the Special Issue.

Papers that analyze aspects related to heat transfer, useful for increasing the knowledge of energy conversion systems, on the basis of one or more of the following topics are also welcome:

  • Energy sources and energy conversion systems
  • Thermodynamic and thermo-economic analysis of energy systems
  • Technologies for renewable energy sources
  • Heating and air conditioning systems
  • Solar thermal and photovoltaic
  • Cogeneration
  • Energy saving
  • Geothermal energy-based systems
  • Waste to energy systems
  • Fuel cells
  • Heat exchangers/heat pipes
  • Heat transfer in porous media
  • Heat transfer in indoor environments
  • Internal flow and heat transfer
  • Multi-phase flows.

Please note that the above list is not exhaustive. Therefore, works focused on other research areas that are relevant for this Special Issue are also appreciated.

This special issue is cooperated with ThermaComp 2020 (http://www.thermacomp.com) which will be held in Budva, Montenegro, June 3-5, 2020. Papers from the conference are welcome.

Prof. Dr. Alessandro Mauro
Prof. Dr. Nicola Massarotti
Prof. Dr. Laura Vanoli
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Energy systems
  • Energy conversion
  • Energy saving
  • Thermo-economic analysis
  • Geothermal energy
  • Cogeneration
  • Waste to energy
  • Conduction
  • Convection
  • Radiation
  • Thermo fluid dynamics
  • Porous media
  • Numerical
  • Experimental
  • Validation
  • Verification

Published Papers (12 papers)

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Research

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36 pages, 6617 KiB  
Article
Off-Design Exergy Analysis of Convective Drying Using a Two-Phase Multispecies Model
by Andrea Aquino and Pietro Poesio
Energies 2021, 14(1), 223; https://doi.org/10.3390/en14010223 - 4 Jan 2021
Cited by 3 | Viewed by 2177
Abstract
The design of a convective drying cycle could be challenging because its thermodynamic performance depends on a wide range of operating parameters. Further, the initial product properties and environmental conditions fluctuate during the production, affecting the final product quality, environmental impact, and energy [...] Read more.
The design of a convective drying cycle could be challenging because its thermodynamic performance depends on a wide range of operating parameters. Further, the initial product properties and environmental conditions fluctuate during the production, affecting the final product quality, environmental impact, and energy usage. An off-design analysis distinguishes the effects of different parameters defining the setup with the best and more stable performance. This study analyzes a reference scenario configured as an existing system and three system upgrades to recover the supplied energy and avoid heat and air dumping in the atmosphere. We calculate their performance for different seasons, initial product moisture, input/output rate, and two products. The analysis comprises 16 simulation cases, the solutions of a two-phase multispecies Euler–Euler model that simulates the thermodynamic equilibrium in all components. Results discuss the combination of parameters that maximizes the evaporation rate and produces the highest benefits on global performance up to doubling the reference levels. The advantages of heat recovery vary by the amount of wasted energy, increasing the exergy efficiency by a maximum of 17%. Energy needs for air recirculation cut the performance at least by 50%. Concluding remarks present the technical guidelines to reduce energy use and optimize production. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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13 pages, 3960 KiB  
Article
Effects of Welding Time and Electrical Power on Thermal Characteristics of Welding Spatter for Fire Risk Analysis
by Yeon Je Shin and Woo Jun You
Energies 2020, 13(24), 6502; https://doi.org/10.3390/en13246502 - 9 Dec 2020
Cited by 3 | Viewed by 2450
Abstract
To predict the fire risk of spatter generated during shielded metal arc welding, the thermal characteristics of welding spatter were analyzed according to different welding times and electrical powers supplied to the electrode. An experimental apparatus for controlling the contact angle between the [...] Read more.
To predict the fire risk of spatter generated during shielded metal arc welding, the thermal characteristics of welding spatter were analyzed according to different welding times and electrical powers supplied to the electrode. An experimental apparatus for controlling the contact angle between the electrode and base metal as well as the feed rate was prepared. Moreover, the correlations among the volume, maximum diameter, scattering velocity, maximum number, and maximum temperature of the welding spatter were derived using welding power from 984–2067 W and welding times of 30 s, 50 s, and 70 s. It was found that the volume, maximum diameter, and maximum number of welding spatters increased proportionally as the welding time and electrical power increased, but the scattering velocity decreased as the particle diameter increased regardless of the welding time and electrical power. When the measured maximum temperature of the welding spatter was compared with an empirical formula, the accuracy of the results was confirmed to be within ±7% of the experimental constant C=112.414×Pe0.5045. Results of this study indicate quantitatively predicting the thermal characteristics of welding spatter is possible for minimizing the risk of fire spread when the electrode type and welding power is known. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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18 pages, 5808 KiB  
Article
Thermodynamic Modeling and Performance Analysis of a Combined Power Generation System Based on HT-PEMFC and ORC
by Hyun Sung Kang, Myong-Hwan Kim and Yoon Hyuk Shin
Energies 2020, 13(23), 6163; https://doi.org/10.3390/en13236163 - 24 Nov 2020
Cited by 10 | Viewed by 2492
Abstract
Recently, the need for energy-saving and eco-friendly energy systems is increasing as problems such as rapid climate change and air pollution are getting more serious. While research on a power generation system using hydrogen energy-based fuel cells, which rarely generates harmful substances unlike [...] Read more.
Recently, the need for energy-saving and eco-friendly energy systems is increasing as problems such as rapid climate change and air pollution are getting more serious. While research on a power generation system using hydrogen energy-based fuel cells, which rarely generates harmful substances unlike fossil fuels, is being done, a power generation system that combines fuel cells and Organic Rankine Cycle (ORC) is being recognized. In the case of High Temperature Proton Exchange Membrane Fuel Cell (HT-PEMFC) with an operating temperature of approximately 150 to 200 °C, the importance of a thermal management system increases. It also produces the waste heat energy at a relatively high temperature, so it can be used as a heat source for ORC system. In order to achieve this outcome, waste heat must be used on a limited scale within a certain range of the temperature of the stack coolant. Therefore, it is necessary to utilize the waste heat of ORC system reflecting the stack thermal management and to establish and predict an appropriate operating range. By constructing an analytical model of a combined power generation system of HT-PEMFC and ORC systems, this study compares the stack load and power generation performance and efficiency of the system by operating temperature. In the integrated lumped thermal capacity model, the effects of stack operating temperature and current density, which are important factors affecting the performance change of HT-PEMFC and ORC combined cycle power generation, were compared according to operating conditions. In the comparison of the change in power and waste heat generation of the HT-PEMFC stack, it was shown that the rate of change in power and waste heat generation by the stack operating temperature was clearly changed according to the current density. In the case of the ORC system, changes in the thermal efficiency of the ORC system according to the operating temperature of the stack and the environmental temperature (cooling temperature) of the object to which this system is applied were characteristic. This study is expected to contribute to the establishment of an optimal operation strategy and efficient system configuration according to the subjects of the HT-PEMFC and ORC combined power generation system in the future. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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16 pages, 2381 KiB  
Article
Entropy Generation in a Dissipative Nanofluid Flow under the Influence of Magnetic Dissipation and Transpiration
by Dianchen Lu, Muhammad Idrees Afridi, Usman Allauddin, Umer Farooq and Muhammad Qasim
Energies 2020, 13(20), 5506; https://doi.org/10.3390/en13205506 - 21 Oct 2020
Cited by 13 | Viewed by 2135
Abstract
The present study explores the entropy generation, flow, and heat transfer characteristics of a dissipative nanofluid in the presence of transpiration effects at the boundary. The non-isothermal boundary conditions are taken into consideration to guarantee self-similar solutions. The electrically conducting nanofluid flow is [...] Read more.
The present study explores the entropy generation, flow, and heat transfer characteristics of a dissipative nanofluid in the presence of transpiration effects at the boundary. The non-isothermal boundary conditions are taken into consideration to guarantee self-similar solutions. The electrically conducting nanofluid flow is influenced by a magnetic field of constant strength. The ultrafine particles (nanoparticles of Fe3O4/CuO) are dispersed in the technological fluid water (H2O). Both the base fluid and the nanofluid have the same bulk velocity and are assumed to be in thermal equilibrium. Tiwari and Dass’s idea is used for the mathematical modeling of the problem. Furthermore, the ultrafine particles are supposed to be spherical, and Maxwell Garnett’s model is used for the effective thermal conductivity of the nanofluid. Closed-form solutions are derived for boundary layer momentum and energy equations. These solutions are then utilized to access the entropy generation and the irreversibility parameter. The relative importance of different sources of entropy generation in the boundary layer is discussed through various graphs. The effects of space free physical parameters such as mass suction parameter (S), viscous dissipation parameter (Ec), magnetic heating parameter (M), and solid volume fraction (ϕ) of the ultrafine particles on the velocity, Bejan number, temperature, and entropy generation are elaborated through various graphs. It is found that the parabolic wall temperature facilitates similarity transformations so that self-similar equations can be achieved in the presence of viscous dissipation. It is observed that the entropy generation number is an increasing function of the Eckert number and solid volume fraction. The entropy production rate in the Fe3O4H2O nanofluid is higher than that in the CuOH2O nanofluid under the same circumstances. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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19 pages, 7993 KiB  
Article
Comparative Analysis of Effectiveness of Resistance and Induction Turnout Heating
by Elzbieta Szychta and Leszek Szychta
Energies 2020, 13(20), 5262; https://doi.org/10.3390/en13205262 - 10 Oct 2020
Cited by 11 | Viewed by 2598
Abstract
Turnouts are key parts of rail roads and are exposed to adverse weather conditions such as snowfall, snow drifts, low temperatures, or sleet. Effective protection assures good turnout function and contributes to rail traffic efficiency and safety. Presently, resistance heating (RH) is the [...] Read more.
Turnouts are key parts of rail roads and are exposed to adverse weather conditions such as snowfall, snow drifts, low temperatures, or sleet. Effective protection assures good turnout function and contributes to rail traffic efficiency and safety. Presently, resistance heating (RH) is the most common system of turnout heating in Europe. In this study, we attempted to implement energy-saving induction heating (IH) in order to cut costs of operation and electricity. A turnout heating test stand, including a stock-rail and a switch-rail, was executed in a climatic chamber. Air temperature was constant at the time of heating. Active power received by both the systems was identical for any measurement (450 W). Test results enabled an assessment of switch-rail position and variations of climatic chamber air temperature on growth of turnout temperatures. Effects of heating type on correct lubrication of the slide plate surface were compared. Dynamics of heating variations and their impact on effectiveness of snow or ice removal were defined for both heating systems. Turnout’s readiness for switch-rail shifting and lubrication conditions of turnout’s moving parts were compared. An in-depth comparative analysis of efficiency of RH and IH turnout heating was undertaken in the conclusion. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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19 pages, 7958 KiB  
Article
Thermal Analysis Strategy for Axial Permanent Magnet Coupling Combining FEM with Lumped-Parameter Thermal Network
by Xikang Cheng, Wei Liu, Ziliang Tan, Zhilong Zhou, Binchao Yu, Wenqi Wang, Yang Zhang and Sitong Liu
Energies 2020, 13(19), 5019; https://doi.org/10.3390/en13195019 - 24 Sep 2020
Cited by 2 | Viewed by 2213
Abstract
Thermal analysis is exceptionally important for operation safety of axial permanent magnet couplings (APMCs). Combining a finite element method (FEM) with a lumped-parameter thermal network (LPTN) is an effective yet simple thermal analysis strategy for an APMC that is developed in this paper. [...] Read more.
Thermal analysis is exceptionally important for operation safety of axial permanent magnet couplings (APMCs). Combining a finite element method (FEM) with a lumped-parameter thermal network (LPTN) is an effective yet simple thermal analysis strategy for an APMC that is developed in this paper. Also, some assumptions and key considerations are firstly given before analysis. The loss, as well as the magnetic field distribution of the conductor sheet (CS) can be accurately calculated through FEM. Then, the loss treated as source node loss is introduced into the LPTN model to obtain the temperature results of APMCs, where adjusting conductivity of the CS is a necessary and significant link to complete an iterative calculation process. Compared with experiment results, this thermal analysis strategy has good consistency. In addition, a limiting and safe slip speed can be determined based on the demagnetization temperature permanent magnet (PM). Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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22 pages, 9607 KiB  
Article
Simulation of the GOx/GCH4 Multi-Element Combustor Including the Effects of Radiation and Algebraic Variable Turbulent Prandtl Approaches
by Evgenij Strokach, Igor Borovik and Oscar Haidn
Energies 2020, 13(19), 5009; https://doi.org/10.3390/en13195009 - 23 Sep 2020
Cited by 4 | Viewed by 2274
Abstract
Multi-element thrusters operating with gaseous oxygen (GOX) and methane (GCH4) have been numerically studied and the results were compared to test data from the Technical University of Munich (TUM). A 3D Reynolds Averaged Navier–Stokes Equations (RANS) approach using a 60° sector as a [...] Read more.
Multi-element thrusters operating with gaseous oxygen (GOX) and methane (GCH4) have been numerically studied and the results were compared to test data from the Technical University of Munich (TUM). A 3D Reynolds Averaged Navier–Stokes Equations (RANS) approach using a 60° sector as a simulation domain was used for the studies. The primary goals were to examine the effect of the turbulent Prandtl number approximations including local algebraic approaches and to study the influence of radiative heat transfer (RHT). Additionally, the dependence of the results on turbulence modeling was studied. Finally, an adiabatic flamelet approach was compared to an Eddy-Dissipation approach by applying an enhanced global reaction scheme. The normalized and absolute pressures, the integral and segment averaged heat flux were taken as an experimental reference. The results of the different modeling approaches were discussed, and the best performing models were chosen. It was found that compared to other discussed approaches, the BaseLine Explicit Algebraic Reynolds Stress Model (BSL EARSM) provided more physical behavior in terms of mixing, and the adiabatic flamelet was more relevant for combustion. The effect of thermal radiation on the wall heat flux (WHF) was high and was strongly affected by spectral models and wall thermal emissivity. The obtained results showed good agreement with the experimental data, having a small underestimation for pressures of around 2.9% and a good representation of the integral wall heat flux. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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14 pages, 4320 KiB  
Article
Experimental Study on a Thermoelectric Generator for Industrial Waste Heat Recovery Based on a Hexagonal Heat Exchanger
by Rui Quan, Tao Li, Yousheng Yue, Yufang Chang and Baohua Tan
Energies 2020, 13(12), 3137; https://doi.org/10.3390/en13123137 - 17 Jun 2020
Cited by 13 | Viewed by 3295
Abstract
To study on the thermoelectric power generation for industrial waste heat recovery applied in a hot-air blower, an experimental thermoelectric generator (TEG) bench with the hexagonal heat exchanger and commercially available Bi2Te3 thermoelectric modules (TEMs) was established, and its performance [...] Read more.
To study on the thermoelectric power generation for industrial waste heat recovery applied in a hot-air blower, an experimental thermoelectric generator (TEG) bench with the hexagonal heat exchanger and commercially available Bi2Te3 thermoelectric modules (TEMs) was established, and its performance was analyzed. The influences of several important influencing factors such as heat exchanger material, inlet gas temperature, backpressure, coolant temperature, clamping pressure and external load current on the output power and voltage of the TEG were comparatively tested. Experimental results show that the heat exchanger material, inlet gas temperature, clamping pressure and hot gas backpressure significantly affect the temperature distribution of the hexagonal heat exchanger, the brass hexagonal heat exchanger with lower backpressure and coolant temperature using ice water mixture enhance the temperature difference of TEMs and the overall output performance of TEG. Furthermore, compared with the flat-plate heat exchanger, the designed hexagonal heat exchanger has obvious advantages in temperature uniformity and low backpressure. When the maximum inlet gas temperature is 360 °C, the maximum hot side temperature of TEMs is 269.2 °C, the maximum clamping pressure of TEMs is 360 kg/m2, the generated maximum output power of TEG is approximately 11.5 W and the corresponding system efficiency is close to 1.0%. The meaningful results provide a good guide for the system optimization of low backpressure and temperature-uniform TEG, and especially demonstrate the promising potential of using brass hexagonal heat exchanger in the automotive exhaust heat recovery without degrading the original performance of internal combustion engine. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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13 pages, 4050 KiB  
Article
Design and Comparison of Resonant and Non-Resonant Single-Layer Microwave Heaters for Continuous Flow Microfluidics in Silicon-Glass Technology
by Tomislav Markovic, Ilja Ocket, Adrijan Baric and Bart Nauwelaers
Energies 2020, 13(10), 2635; https://doi.org/10.3390/en13102635 - 21 May 2020
Cited by 8 | Viewed by 2682
Abstract
This paper presents a novel concept for the co-design of microwave heaters and microfluidic channels for sub-microliter volumes in continuous flow microfluidics. Based on the novel co-design concept, two types of heaters are presented, co-designed and manufactured in high-resistivity silicon-glass technology, resulting in [...] Read more.
This paper presents a novel concept for the co-design of microwave heaters and microfluidic channels for sub-microliter volumes in continuous flow microfluidics. Based on the novel co-design concept, two types of heaters are presented, co-designed and manufactured in high-resistivity silicon-glass technology, resulting in a building block for consumable and mass-producible micro total analysis systems. Resonant and non-resonant co-planar waveguide transmission line heaters are investigated for heating of sub-micro-liter liquid volumes in a channel section at 25 GHz. The heating rates of 16 and 24 °C/s are obtained with power levels of 32 dBm for the through line and the open-ended line microwave heater, respectively. The heating uniformity of developed devices is evaluated with a Rhodamine B and deionized water mixture on a micrometer scale using the microwave-optical measurement setup. Measurement results showed a good agreement with simulations and demonstrated the potential of microwave heating for microfluidics. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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24 pages, 8052 KiB  
Article
Modeling Artificial Ground Freezing for Construction of Two Tunnels of a Metro Station in Napoli (Italy)
by Alessandro Mauro, Gennaro Normino, Filippo Cavuoto, Pasquale Marotta and Nicola Massarotti
Energies 2020, 13(5), 1272; https://doi.org/10.3390/en13051272 - 10 Mar 2020
Cited by 24 | Viewed by 4191
Abstract
An artificial ground freezing (AGF) technique in the horizontal direction has been employed in Naples (Italy), in order to ensure the stability and waterproofing of soil during the excavation of two tunnels in a real underground station. The artificial freezing technique consists of [...] Read more.
An artificial ground freezing (AGF) technique in the horizontal direction has been employed in Naples (Italy), in order to ensure the stability and waterproofing of soil during the excavation of two tunnels in a real underground station. The artificial freezing technique consists of letting a coolant fluid, with a temperature lower than the surrounding ground, circulate inside probes positioned along the perimeter of the gallery. In this paper, the authors propose an efficient numerical model to analyze heat transfer during the whole excavation process for which this AGF technique was used. The model takes into account the water phase change process, and has been employed to analyze phenomena occurring in three cross sections of the galleries. The aim of the work is to analyze the thermal behavior of the ground during the freezing phases, to optimize the freezing process, and to evaluate the thickness of frozen wall obtained. The steps to realize the entire excavation of the tunnels, and the evolution of the frozen wall during the working phases, have been considered. In particular, the present model has allowed us to calculate the thickness of the frozen wall equal to 2.1 m after fourteen days of nitrogen feeding. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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16 pages, 5786 KiB  
Article
Investigation of Start-Up Characteristics of Thermosyphons Modified with Different Hydrophilic and Hydrophobic Inner Surfaces
by Xiaolong Ma, Zhongchao Zhao, Pengpeng Jiang, Shan Yang, Shilin Li and Xudong Chen
Energies 2020, 13(3), 765; https://doi.org/10.3390/en13030765 - 9 Feb 2020
Cited by 5 | Viewed by 3009
Abstract
In this paper, the influence of wettability properties on the start-up characteristics of two-phase closed thermosyphons (TPCTs) is investigated. Chemical coating and etching techniques are performed to prepare the surfaces with different wettabilities that is quantified in the form of the contact angle [...] Read more.
In this paper, the influence of wettability properties on the start-up characteristics of two-phase closed thermosyphons (TPCTs) is investigated. Chemical coating and etching techniques are performed to prepare the surfaces with different wettabilities that is quantified in the form of the contact angle (CA). The 12 TPCTs are processed including the same CA and a different CA combination on the inner surfaces inside both the evaporator and the condenser sections. For TPCTs with the same wettability properties, the introduction of hydrophilic properties inside the evaporator section not only significantly reduces the start-up time but also decreases the start-up temperature. For example, the start-up time of a TPCT with CA = 28° at 40 W, 60 W and 80 W is 46%, 50% and 55% shorter than that of a TPCT with a smooth surface and the wall superheat degrees is 55%, 39% and 28% lower, respectively. For TPCTs with combined hydrophilic and hydrophobic properties, the start-up time spent on the evaporator section with hydrophilic properties is shorter than that of the hydrophobic evaporator section and the smaller CA on the condenser section shows better results. The start-up time of a TPCT with CA = 28° on the evaporator section and CA = 105° on the condenser section has the best start-up process at 40 W, 60 W and 80 W which is 14%, 22% and 26% shorter than that of a TPCT with smooth surface. Thus, the hydrophilic and hydrophobic modifications play a significant role in promoting the start-up process of a TPCT. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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Review

Jump to: Research

0 pages, 640 KiB  
Review
Smart Asset Management for District Heating Systems in the Baltic Sea Region
by Anna Grzegórska, Piotr Rybarczyk, Valdas Lukoševičius, Joanna Sobczak and Andrzej Rogala
Energies 2021, 14(2), 314; https://doi.org/10.3390/en14020314 - 8 Jan 2021
Cited by 10 | Viewed by 3249 | Correction
Abstract
The purpose of this review is to provide insight and a comparison of the current status of district heating (DH) systems for selected Baltic Sea countries (Denmark, Germany, Finland, Latvia, Lithuania, Poland, and Sweden), especially from viewpoints of application and solutions of novel [...] Read more.
The purpose of this review is to provide insight and a comparison of the current status of district heating (DH) systems for selected Baltic Sea countries (Denmark, Germany, Finland, Latvia, Lithuania, Poland, and Sweden), especially from viewpoints of application and solutions of novel smart asset management (SAM) approaches. Furthermore, this paper considers European projects ongoing from 2016, involving participants from the Baltic Sea Region, concerning various aspects of DH systems. The review presents the energy sources with particular attention to renewable energy sources (RES), district heating generations, and the exploitation problems of DH systems. The essential point is a comparison of traditional maintenance systems versus SAM solutions for optimal design, operating conditions, and controlling of the DH networks. The main conclusions regarding DH systems in Baltic Sea countries are commitment towards a transition to 4th generation DH, raising the quality and efficiency of heat supply systems, and simultaneously minimizing the costs. The overall trends show that applied technologies aim to increase the share of renewable energy sources and reduce greenhouse gas emissions. Furthermore, examples presented in this review underline the importance of the implementation of a smart asset management concept to modern DH systems. Full article
(This article belongs to the Special Issue Heat Transfer in Energy Conversion Systems)
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