Haixu Teng , Ming Li , Jun Wang , Shuangyuan Xiong , Chunhong Lu , Zhanzhuo Song , Haikang Chen , Yan Jiang
{"title":"Energy utilization of CO2 thermal management system for electric vehicles in cold climate: Assessment of different heat source modes","authors":"Haixu Teng , Ming Li , Jun Wang , Shuangyuan Xiong , Chunhong Lu , Zhanzhuo Song , Haikang Chen , Yan Jiang","doi":"10.1016/j.ijrefrig.2025.03.025","DOIUrl":"10.1016/j.ijrefrig.2025.03.025","url":null,"abstract":"<div><div>To further improve the heating energy efficiency at low temperatures, this study analyzes the feasibility of a CO<sub>2</sub> electric vehicle (EV) utilizing different heat source (air source, waste heat-only, and dual-source) modes under low-temperature conditions. Initially, the difference in heating energy efficiency between air source and waste heat-only modes was compared at different supply air temperatures of -10°C. Concurrently, the dual heat source mode was evaluated at -20°C, emphasizing the impact of the electronic expansion valve 3 (EEV3) opening on heating performance at different constant coolant temperatures. This study presents an evaluation method for heating performance, and the temperature rise characteristics of a real vehicle in air source mode at -20°C are validated through environmental chamber experiments. The results indicate that the inner gas cooler outlet refrigerant temperature strongly correlates with the maximum heating capacity. When the supply air temperature is set to 50°C, the compressor power consumption in the waste heat-only mode decreases by 12.9 % compared with the air source mode, and the COP increases by 13.5 %. As the supply air temperature rises, the efficiency improvements of the COP gradually decrease. Compared with the air source mode, the heating capacity of the dual heat source mode increased by 6.4 %-19.2 %, the COP improved by 4.5 %-5.7 %, and the driving range improved by 9.4 %-15.6 %. This study demonstrates that the thermal management system can meet the temperature rise characteristics, and the maximum outlet air temperature of the air source mode reaches 56.83°C at -20°C.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 359-371"},"PeriodicalIF":3.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exergy-energy, economic and environmental evaluation of a solid oxide fuel cell based trigeneration system using double effect vapor absorption refrigeration system","authors":"Yunis Khan , Pawan Kumar Singh , Aftab Anjum , K.K. Sivakumar , Shikha Gupta , Subhash Mishra","doi":"10.1016/j.ijrefrig.2025.03.029","DOIUrl":"10.1016/j.ijrefrig.2025.03.029","url":null,"abstract":"<div><div>In this work, a heat recovery steam generator (HRSG) and double-effect absorption refrigeration system (DVARS) have been implemented in conventional hybrid solid oxide fuel cell (SOFC)-gas turbines (GT) for applications like power generation, steam production, and cooling effects for industrial purposes. The performance of the proposed trigeneration system has been evaluated numerically on the basis of thermodynamic, economic, and environmental aspects using engineering equation software. The results show that by implementing the HRSG and DVARS in the conventional SOFC-GT system, energy efficiency, exergy efficiency, and the total cost of the proposed trigeneration plant (SOFC-GT-HRSG-DVARS) were enhanced by 36.51 %, 4.14 %, and 1.76 %, respectively. Additionally, cooling effects of 100 kW were obtained from the DVARS at 5 °C for general-purpose applications, and heating effects of 101.4 kW were obtained through the HRSG by generating saturated steam. However, the CO<sub>2</sub> emission per MWh of output energy was reduced by 26.73 %.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 343-358"},"PeriodicalIF":3.5,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experimental improvement of a CO2 transcritical cycle using parallel compressor and integrated subcooler","authors":"R. Larrondo-Sancho, D. Sánchez, R. Cabello","doi":"10.1016/j.ijrefrig.2025.03.019","DOIUrl":"10.1016/j.ijrefrig.2025.03.019","url":null,"abstract":"<div><div>Due to the low critical temperature of Carbon Dioxide (CO<sub>2</sub>), the simplest CO<sub>2</sub> transcritical refrigeration cycle is usually upgraded with different configurations to enhance the performance, increase the cooling capacity, and reduce the flash-gas generated during the expansion process. Considering this, different arrangements were proposed over time with excellent results but rarely compared in a unique refrigeration plant. The present work experimentally analyses and compares three-cycle arrangements for CO<sub>2</sub> transcritical cycles, adding an internal heat exchanger (IHX), a parallel compressor, and an integrated subcooler.</div><div>Taking the IHX arrangement as a reference, the parallel compression and the integrated subcooler are compared at the heat rejection temperatures of 20, 27, and 34°C for commercial refrigeration purposes. The combination of parallel compressor and IHX provides maximum coefficient of performance (COP) and cooling capacity improvements of 3.6 % and 18.5 %, respectively, while the combination of integrated subcooler and IHX boosts the COP and the cooling capacity by up to 11.0 % and 19.5 %, respectively. The results demonstrate the convenience of using these configurations, fairly comparing arrangements with the same refrigerating plant.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 63-73"},"PeriodicalIF":3.5,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tu Aimin , Lin Zhongxuan , Zhan Xuefeng , Yin Jiying , Liu Shijie , Zhu Dongsheng
{"title":"Simulation and experimental verification of cooling thermal performance of vertical tube downflow composite evaporative cooling tower","authors":"Tu Aimin , Lin Zhongxuan , Zhan Xuefeng , Yin Jiying , Liu Shijie , Zhu Dongsheng","doi":"10.1016/j.ijrefrig.2025.03.023","DOIUrl":"10.1016/j.ijrefrig.2025.03.023","url":null,"abstract":"<div><div>The thermal performance of a vertical tube downflow composite evaporative cooling tower(VTD-CECT) with three-dimensional tubes was simulated under engineering application conditions. The effects of different ambient air conditions, different hot water inlet temperatures, and different spray densities on the cooling performance of VTD-CECT were analyzed. The performance test of the experimental prototype was carried out and compared with the simulated values, and the results show that the established VTD-CECT thermal performance prediction model has a good prediction effect. Analyzed the impact of packing to enhance the cooling capacity of evaporative cooling tower, the results show that in the case of 50 % of the cooling airflow through the packing, in the range of adjustable test conditions can enhance the cooling capacity of the VTD-CECT 31.7 % ∼ 40.8 %, reduce the spray water temperature of 0.94 ∼ 2.79 °C, and the reduction in metal usage is significant. A methodology for evaluating the cooling capacity of closed cooling towers is proposed. This study can provide a reference for the engineering application of the VTD-CECT.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 85-94"},"PeriodicalIF":3.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R.M.A. Spijkers , A. Damas , Z. Zhang , S. Vanapalli
{"title":"Assessment of the thermal performance of a dry-shipper used in deep frozen cold chain","authors":"R.M.A. Spijkers , A. Damas , Z. Zhang , S. Vanapalli","doi":"10.1016/j.ijrefrig.2025.03.014","DOIUrl":"10.1016/j.ijrefrig.2025.03.014","url":null,"abstract":"<div><div>A dry shipper is a vacuum insulated transport container with a liquid nitrogen filled porous lining inside to transport frozen biomedical samples. The current understanding of the thermal characteristics of vacuum insulated vessels is based on standard cryostats, where the liquid collects in a pool at the bottom accompanied by a stratified vapor above it, wherein the temperature increases with height. However, the behavior of a dry-shipper diverges significantly from these standard cryostats, since the liquid is contained within a porous lining rather than at the vessel’s base, stratification is absent. The current thermal models for standard cryostats cannot be applied to a dry-shipper due to the difference in temperature profile, therefore the thermal characteristics of a dry-shipper are investigated. We present experimental data of an instrumented dry-shipper subjected to various simulated conditions, namely the ambient temperature is varied from 295 K to 333 K and the positioning is varied from upright to an angle of 45°and 90°. We observed that the mass of the dry-shipper reduced linearly with time, which corresponds to a constant evaporation rate of the liquid nitrogen in the container. A simplified model is developed to predict the liquid nitrogen evaporation rate in the dry-shipper as a function of ambient conditions, giving indirect measurement of the liquid nitrogen in the container. This will aid shipping firms to plan the transport as well as develop smart versions of the dry-shipper.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 156-163"},"PeriodicalIF":3.5,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Novel concept of magnetocaloric heat pipe and its micro-unit regeneration cycle","authors":"Fucheng Chen, Jianghong Wu","doi":"10.1016/j.ijrefrig.2025.03.024","DOIUrl":"10.1016/j.ijrefrig.2025.03.024","url":null,"abstract":"<div><div>Magnetocaloric Refrigeration (MR) presents a viable alternative to the Vapor Compression Cycle (VCC). The Active Magnetic Regenerator (AMR) has thus far been hindered by challenges related to low operational frequencies and inadequate heat transfer coefficients. The Micro-Unit Regeneration (MUR) cycle demonstrates nearly flawless performance within the caloric thermodynamic cycle, but its fully solid-state prototype suffers from extremely low thermal conductivity, rendering it impractical for real-world applications. This paper introduces a novel concept of Magnetocaloric Heat Pipe (MCHP). It integrates Magnetocaloric Effect (MCE) with phase change heat transfer to enhance heat transfer efficiency between Magnetocaloric Materials (MCMs). A MCHP-MUR cycle for magnetic heat pump is developed, a small temperature difference between micro-unit of MCMs drives the evaporation-condensation phase change heat regeneration. Additionally, a thermal resistance model of the MCHP unit and multi-stage MUR cycle are constructed for performance evaluation at 1.5 T magnetic intensity. Experimental results indicate that the heat transfer process, characterized by a small temperature difference of 4.0 K, can be completed and reach equilibrium within 0.5 s, which is a 99 % reduction in equilibrium time compared to solid-state heat conduction. A system temperature span of 3.2 K was attained in basic two-stage MCHP-MUR cycle. In numerical simulations, a dual 16-stage MCHP-MUR cycle demonstrated a maximum no-load temperature span of 25.3 K and a peak heating capacity of 3.5 W g<sup>-1</sup> at zero temperature span. The paper also offers recommendations and discussions that may inform the design and optimization of the innovative MCHP-MUR cycle.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 25-38"},"PeriodicalIF":3.5,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Yang , Jun Zeng , Boyu Yang , Junsong Hu , Ziyan Zhang
{"title":"Study on the energy performance of a multi-mode split evaporative-cooling hybrid air-conditioning system","authors":"Yang Yang , Jun Zeng , Boyu Yang , Junsong Hu , Ziyan Zhang","doi":"10.1016/j.ijrefrig.2025.03.022","DOIUrl":"10.1016/j.ijrefrig.2025.03.022","url":null,"abstract":"<div><div>Reducing energy consumption in buildings is a crucial component in the pursuit of carbon neutrality and sustainable social development. The air-conditioning systems account for a significant portion of a building's energy consumption and therefore require special attention to their energy efficiency. These air-conditioning systems that incorporate indirect evaporative cooling (IEC) technology are a viable energy-saving strategy. However, these hybrid systems are mainly designed for hot-dry climates, and limited research has focused on the coupling advantages of condenser pre-cooling and reheating energy recovery via IEC through different operating modes. In this paper, a novel multi-mode split evaporative-cooling hybrid air-conditioning system (MVC-IEC) is proposed, which utilizes the IEC cycle to achieve condenser pre-cooling and supply air reheating. Simultaneously, it features five operating modes to adapt to the changing ambient climatic conditions. Subsequently, the energy performance of the MVC-IEC system was primarily investigated under different operating conditions. The MVC-IEC demonstrates a more pronounced energy-saving advantage under high temperature, medium-low humidity and low reheat load conditions. In addition, the MVC-IEC has acceptable application potential in both hot-humid and hot-dry cities (Changsha, Nanjing, Zhengzhou and Xi'an). The seasonal COP for the MVC-IEC is reached by 3.9 − 4.6. And compared with MVC<img>HRC, the MVC-IEC achieves an energy-saving rate of 10.8 − 16.3 % and reduces carbon emissions by 0.42−0.80 kg/year.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 217-231"},"PeriodicalIF":3.5,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shicheng Ying, Hang Yin, Guangbin Liu, Qichao Yang, Yuanyang Zhao, Liansheng Li
{"title":"Performance evaluation of ejector-enhanced and gas-bearing-assisted vapor compression chilled water system","authors":"Shicheng Ying, Hang Yin, Guangbin Liu, Qichao Yang, Yuanyang Zhao, Liansheng Li","doi":"10.1016/j.ijrefrig.2025.03.009","DOIUrl":"10.1016/j.ijrefrig.2025.03.009","url":null,"abstract":"<div><div>The centrifugal compressor with gas bearings is an important research direction of chiller, but the essential additional gas cycle for bearing and motor cooling still lead to the energy waste. Using an ejector to increase this gas pressure by recovering the energy of expansion process for inter-stage replenishment is a feasible solution. In this paper, a mathematical model of EGVC system (ejector-enhanced gas-bearing-assisted vapor compression chilled water system) is established and simulated comparing to the BGVC system (basic gas-bearing-assisted vapor compression chilled water system), and the performance under variable working conditions is obtained by 4E (energy, exergy, economic, environmental) analysis method. The results indicate that the ejector can reduce power consumption for gas compression and improving system performance. The COP increases while the exergy efficiency decrease with the evaporating temperature for both systems, but they show opposite changes with condensing temperature. Comparing to BGVC, the COP of EGVC increases by 1.29 %-1.52 % and the exergy efficiency increases by 1.02 %-1.21 % when the evaporating temperature rises from 1 °C to 9 °C, while they increase by 1.41 %-1.63 % and 1.12 %-1.31 % when the condensing temperature increases from 40 °C to 48 °C. The EGVC system is more suitable to the large bearing gas condition, and the COP and exergy efficiency improve by 1.49 %-2.20 % and 1.19 %-1.67 % when the proportion of gas for bearing to the total refrigerant rises from 1 % to 2 %. The cost and carbon emission of system also be reduced by using the ejector.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 185-203"},"PeriodicalIF":3.5,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Conventional and advanced exergy analysis of a dual-evaporator transcritical CO2 refrigeration system enhanced with ejectors","authors":"Jia Yan , Yuetong Shu","doi":"10.1016/j.ijrefrig.2025.03.021","DOIUrl":"10.1016/j.ijrefrig.2025.03.021","url":null,"abstract":"<div><div>Based on two conventional dual-evaporator systems, this study introduces ejectors and combines traditional exergy analysis with advanced exergy analysis to conduct an in-depth comparison and optimization of four systems. The main objective of the study is to refine the exergy loss distribution, evaluate the improvement potential of each component, and provide a basis for system optimization. The results show that the introduction of ejectors significantly reduces the system's exergy losses and improves exergy efficiency, with the dual-evaporator transcritical CO<sub>2</sub> refrigeration cycle with two compressors (ERCC) system performing the best. Under given conditions, the exergy losses of ejector-enhanced dual-evaporator transcritical CO<sub>2</sub> refrigeration cycle with PRV (ERCV) and ERCC systems are reduced to 60 % of those in conventional systems, with exergy efficiencies increased to 53.69 % and 45.28 %, respectively. Additionally, gas cooler pressure has a significant impact on system performance, and the pressure maintaining under 9 MPa can significantly improve exergy efficiency. Advanced exergy analysis reveals that the endogenous exergy destruction is mainly caused by irreversibility, and compressor2 and compressor in ERCC and ERCV should be optimized first, which can improve the system efficiency by 75.36 % and 65.16 %, respectively.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 204-216"},"PeriodicalIF":3.5,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Influence of asymmetrical features of scroll plates on thermodynamic processes and orbiting scroll dynamic characteristics of electric vehicle scroll compressors","authors":"Zibo Zhao, Che Wang, Jianhua Wu","doi":"10.1016/j.ijrefrig.2025.03.020","DOIUrl":"10.1016/j.ijrefrig.2025.03.020","url":null,"abstract":"<div><div>The electric scroll compressor is the main energy-consuming component of the thermal management system of electric vehicles and has been widely used for this application. To meet the needs of the entire vehicle, the scroll compressor is developing towards miniaturization. However, this trend often causes the compressor to have shorter scroll wraps and may require high rotational speeds for operation. As a result, changes in the structures of scroll plates have already appeared, including different lengths between fixed and orbiting scroll wraps, an off-center discharge port, asymmetrically positioned bypass ports, a crescent groove at the start of the orbiting scroll, and scroll wrap offsetting. Although these features, referred to as asymmetrical features in this paper, fundamentally change the thermodynamic process within the scroll chambers and dynamic characteristics of the orbiting scroll plate, no study has comprehensively discussed them or their impacts. Clarifying the mechanism and extent of these features is a worthwhile endeavor that will help guide the future design and optimization of scroll plates. Therefore, a mathematical model of the thermodynamic process and dynamic analysis was established in this study. An experiment was then conducted to confirm the model validation. Four working conditions under different pressure ratios and rotational speeds were selected to perform the simulation. The impacts of the working conditions and asymmetrical features on pressure and temperature changes within the scroll chambers and changes in the forces and moments acting on the orbiting scroll plate were compared and analyzed.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 270-285"},"PeriodicalIF":3.5,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143681031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}