International Journal of Refrigeration-revue Internationale Du Froid最新文献_第4页

Study on the flame retarding mechanism of HFC-134a on hydrocarbon refrigerants

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-20 DOI: 10.1016/j.ijrefrig.2025.02.018

Rui Zhai , Xiang Li , Yuan Zhuang , Bin Ye , Xiangnong Liu , Qingqing Li , Lei Tang , Ke Wang

{"title":"Study on the flame retarding mechanism of HFC-134a on hydrocarbon refrigerants","authors":"Rui Zhai , Xiang Li , Yuan Zhuang , Bin Ye , Xiangnong Liu , Qingqing Li , Lei Tang , Ke Wang","doi":"10.1016/j.ijrefrig.2025.02.018","DOIUrl":"10.1016/j.ijrefrig.2025.02.018","url":null,"abstract":"<div><div>Hydrocarbons (HCs) are ideal candidates for the long-term environmentally friendly refrigerants due to their excellent advantages in environmental protection and energy efficiency. But the flammability properties limit their wide application. To address it, this study focused on the inhibition mechanism of HFC-134a on the combustion processes of hydrocarbon refrigerants (HC-50, HC-170, HC-290 and HC-600a). A kinetic model of HCs/HFC-134a combustion was established to compared the effects of HFC-134a on the adiabatic flame temperature, laminar burning velocity, key species and radical reactions. The results showed that the addition of HFC-134a significantly reduced the adiabatic flame temperatures and laminar burning velocities of hydrocarbons. The concentration analysis of products and rate of production (ROP) revealed that HFC-134a promoted the productions of flame retarding groups CF, CF<sub>2</sub>, CF<sub>3</sub>, and CHF, while consumed the concentrations of flammable radicals H, O, and OH. Furthermore, sensitivity and reaction path analysis proved the suppressing actions of HFC-134a. It was concluded that HFC-134a not only changed the reaction paths and sensitivity coefficients, but also transformed the promotion path into inhibitory path in combustion. These effects achieved effective inhibition on the combustion processes of HCs. The results of this paper not only supported the safe application of hydrocarbon refrigerants, but also provided new ideas for the development of new efficient flame retardants.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 1-13"},"PeriodicalIF":3.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143549957","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}

引用次数: 0

Experimental study on the heating performance of a transcritical CO2 heat pump water heater under Multi-Parameter coordinated matching operation

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-20 DOI: 10.1016/j.ijrefrig.2025.02.019

Rusheng Hu , Xu Jin , Xiaoqiong Li , Youdong Wang , Zhentao Zhang , Zhongyan Liu , Xin Meng

{"title":"Experimental study on the heating performance of a transcritical CO2 heat pump water heater under Multi-Parameter coordinated matching operation","authors":"Rusheng Hu , Xu Jin , Xiaoqiong Li , Youdong Wang , Zhentao Zhang , Zhongyan Liu , Xin Meng","doi":"10.1016/j.ijrefrig.2025.02.019","DOIUrl":"10.1016/j.ijrefrig.2025.02.019","url":null,"abstract":"<div><div>In CO<sub>2</sub> heat pump (HP) water heaters, achieving optimal synergy among operating parameters is essential for maintaining high system performance under varying heating demands. This study investigates a CO<sub>2</sub> HP system equipped with an electronic expansion valve (EEV) and ejector throttling. The comprehensive effects of operating parameters—compressor frequency, EEV opening, inlet water flow rate (IWFR), and temperature—on system performance were quantified through the mean normalization method, along with a comparative analysis of the performance under EEV and ejector throttling modes. The results show that ejector throttling improves the coefficient of performance (<em>COP</em>) by 6.5 %. Within a specific range, reducing the EEV opening improves <em>COP</em>, particularly at lower inlet water temperatures and higher IWFRs, achieving a <em>COP</em> of 3.49 (30 Hz, 60 % EEV, 20 °C, 0.6 m<sup>3</sup>⸳h<sup>−1</sup>). Compressor frequency, IWFR, and temperature are identified as the primary factors influencing heat transfer rate. The impact of compressor frequency and inlet water temperature on <em>COP</em> is more significant than that of IWFR and EEV opening. To meet hot water demand and maintain high system performance, the weighted influence of each parameter must be carefully evaluated during adjustments to ensure system stability and optimal performance. This study offers valuable insights for developing multi-parameter control strategies for CO<sub>2</sub> HP water heaters.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"173 ","pages":"Pages 212-228"},"PeriodicalIF":3.5,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509003","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}

引用次数: 0

FEMCE – A 3D finite element simulation tool for magnetic refrigerants

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-16 DOI: 10.1016/j.ijrefrig.2025.02.017

R. Kiefe, J.S. Amaral

引用次数: 0

Experimental evaluation of the thermoelectric package air conditioning for an automotive interior application

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-15 DOI: 10.1016/j.ijrefrig.2025.02.009

Eid S. mohamed

{"title":"Experimental evaluation of the thermoelectric package air conditioning for an automotive interior application","authors":"Eid S. mohamed","doi":"10.1016/j.ijrefrig.2025.02.009","DOIUrl":"10.1016/j.ijrefrig.2025.02.009","url":null,"abstract":"<div><div>Numerous researchers are developing air conditioning for vehicles. One of the newest techniques for air cooling is thermoelectric package acr conditioning (TEPAC), numerous benefits include its compact size, low weight, and ability to handle direct current sources. However, this study aims to evaluate the effectiveness of the two modes (water /air and air/air) TEPAC system under the 50 min test period. The cooling characteristics of the TEPAC system with eight thermoelectric cooling (TEC) units are experimentally presented. A TEPAC system with a prototype chamber to simulate the automotive interior is proposed to reach the desired temperature of 24 °C. The effects of TEC input electrical current, air flow rate and water flow rate on the cooling performance are measured. A comparative analysis of the overall coefficient of performance (COP<sub>overall</sub>) and electrical power consumption (EPC) has been evaluated for two TEPAC system modes. The COP<sub>overall</sub> the water/air TEPAC mode was more effective than the air/air TEPAC mode in all cases studied. It was found that water/air TEPAC mode generally had higher COP<sub>overall</sub> (18.2: 30 %) than those of the air/air TEPAC mode, and the total EPC in water/air mode was found to be roughly 1.5–4.5 % greater than in air/air mode. The water/air TEPAC mode also proved flexible in maintaining the desired temperature with the pulse width modulation kit (PWMK) technique under % 50 duty cycle. Therefore, the water/air TEPAC mode is more effective for use in automotive interior air conditioning.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 34-46"},"PeriodicalIF":3.5,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561986","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}

引用次数: 0

Theoretical investigation on the performance of R600/R170/R14/R50 four stage regenerator-enhanced auto cascade refrigeration system

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-14 DOI: 10.1016/j.ijrefrig.2025.02.004

Yongning He , Su'ao Wang , Wenliang Cao , Huihong Wu , Xuehong Wu , Linfen Xing

{"title":"Theoretical investigation on the performance of R600/R170/R14/R50 four stage regenerator-enhanced auto cascade refrigeration system","authors":"Yongning He , Su'ao Wang , Wenliang Cao , Huihong Wu , Xuehong Wu , Linfen Xing","doi":"10.1016/j.ijrefrig.2025.02.004","DOIUrl":"10.1016/j.ijrefrig.2025.02.004","url":null,"abstract":"<div><div>In multi-stage auto cascade refrigeration (ACR) systems, the component selection and ratio optimization of zeotropic mixed refrigerants is important. A four-stage regenerator-enhanced ACR (RACR) system using R600/R170/R14/R50 was proposed. Influences of refrigerant mixture ratio, high-boiling-point components, gas-phase fraction before throttling (<em>x</em><sub>4</sub>) and gas-liquid separation temperature (<em>T</em><sub>S1</sub>∼<em>T</em><sub>S3</sub>) on the system performance were explored. Exergy loss ratios of components were compared and analyzed. The results demonstrated that increasing the mass fraction of R170 and reducing that of R50 significantly improve the energy efficiency, and reduce discharge temperature. To obtain -140 °C, a minimum <em>x</em><sub>4</sub> (<em>x</em><sub>4</sub> <sub>min</sub>) could optimize the coefficient of performance (COP). R600/R170/R14/R50 (mass fraction of 0.38/0.20/0.17/0.25 and <em>x</em><sub>4</sub> <sub>min</sub> of 0.12) had the best COP of 0.192 and exergy efficiency of 0.330 under variable <em>x</em><sub>4</sub> conditions. To improve the energy efficiency, appropriately reducing <em>T</em><sub>S1</sub> and <em>T</em><sub>S3</sub>, or increasing <em>T</em><sub>S2</sub> could be adopted. The top three components in the RACR system accounted for the largest exergy loss proportion were compressor, throttle at the evaporator inlet and condenser, accounting for 26.0 %, 18.3 % and 15.7 %, respectively.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 14-22"},"PeriodicalIF":3.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143549958","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}

引用次数: 0

Detailed study of a condensation-driven dilution refrigerator reaching below 50 mK

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-14 DOI: 10.1016/j.ijrefrig.2025.02.016

Weijun Cheng , Zhiheng Li , Yanan Wang , Wei Dai

{"title":"Detailed study of a condensation-driven dilution refrigerator reaching below 50 mK","authors":"Weijun Cheng , Zhiheng Li , Yanan Wang , Wei Dai","doi":"10.1016/j.ijrefrig.2025.02.016","DOIUrl":"10.1016/j.ijrefrig.2025.02.016","url":null,"abstract":"<div><div>The condensation-driven dilution refrigerator employs a condensation pump to accomplish the circulation of <sup>3</sup>He, offering advantages such as compactness, lightweight, and low cost. In our previous work, we constructed a prototype with a lowest temperature of around 60 mK, yet the system performance needs further improvement. In this paper, we present our latest advances. By adding a step heat exchanger made from sintered silver powder and reducing heat leakage in the system, a lowest temperature of 45 mK, a maximum cooling power of 8.4 μW @100 mK, and a corresponding thermodynamic degree of perfection of 11.28 % is achieved in the experiments. A comprehensive numerical model of the condensation-driven dilution refrigerator has been developed. The results of experiments and simulations are compared and analyzed, revealing the influence of key parameters on the system performance. Firstly, the efficiency is significantly related to the temperature of the mixing chamber, still, and condensation pump. The entropy generation analysis is conducted, and it is found that the contribution of the still to the total entropy production always remains predominant. Secondly, to circulate the <sup>3</sup>He, the vapor pressure above the still should be greater than the saturated vapor pressure corresponding to the condensation pump temperature. This imposes a requirement on both the still and condensation pump temperatures to activate the dilution cycle with a certain mixing chamber temperature. Finally, the comparison between the experiments and simulations indicates a maximum cooling power exists at a certain high still temperature as the other conditions are kept the same. With the help of the simulation, the internal dynamic and thermodynamic characteristics during operation have been clarified, which can guide further optimizations.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"173 ","pages":"Pages 201-211"},"PeriodicalIF":3.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143487556","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}

引用次数: 0

Thermodynamic and environment analysis of a modified transcritical CO2 refrigeration cycle integrated with ejector and subcooler

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-13 DOI: 10.1016/j.ijrefrig.2025.02.012

Lingeng Zou , Ye Liu , Jianlin Yu

{"title":"Thermodynamic and environment analysis of a modified transcritical CO2 refrigeration cycle integrated with ejector and subcooler","authors":"Lingeng Zou , Ye Liu , Jianlin Yu","doi":"10.1016/j.ijrefrig.2025.02.012","DOIUrl":"10.1016/j.ijrefrig.2025.02.012","url":null,"abstract":"<div><div>The traditional transcritical CO<sub>2</sub> two-stage compression refrigeration cycle (TTRC) has a great advantage in supermarket refrigeration applications. Currently, however, the performance of the TTRC still has the potential to be improved. In this paper, an ejector-enhanced transcritical two-stage compression CO<sub>2</sub> cycle is presented for supermarket refrigeration application. Based on the basic TTRC with a subcooler, a flash tank, an ejector and are introduced. On the one hand, part of the expansion work can be recovered by the ejector. Moreover, the subcooler is employed to increase the subcooling degree of refrigerant entering the expansion valve, which could increase the evaporator's cooling capacity. The cycle performances of the cycles are theoretically studied by energy, exergy and carbon footprint evaluation. Meanwhile, the intermediate pressures of the two cycles are also optimized. Under optimum intermediate pressure, the energy analyses show that the coefficient of performance is improved by 9.6–11.0% and the volume cooling capacity is enhanced by 14.5%-18.4% with the modified cycle. Moreover, the exergy analysis indicates that the expansion valves account for 27.1% of the exergy destruction of the basic cycle, while it is just 7.51% for the modified cycle. The carbon footprint analysis shows that the modified system with CO<sub>2</sub> refrigerant could reduce carbon emissions by 17.95% compared to the conventional refrigerant R404A. It shows the feasibility of using CO<sub>2</sub> to replace R404A refrigerant in commercial supermarket refrigeration, and has significant eco-friendly benefits.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"173 ","pages":"Pages 123-138"},"PeriodicalIF":3.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445710","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}

引用次数: 0

Dynamic synergy optimization (DSO): An integrated approach of metaheuristic algorithms and PID control for real-time stability enhancement in refrigeration systems

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-13 DOI: 10.1016/j.ijrefrig.2025.02.015

Jieyu Li, Xingxiang Xie, Leyang Dai, Lijie Xu

{"title":"Dynamic synergy optimization (DSO): An integrated approach of metaheuristic algorithms and PID control for real-time stability enhancement in refrigeration systems","authors":"Jieyu Li, Xingxiang Xie, Leyang Dai, Lijie Xu","doi":"10.1016/j.ijrefrig.2025.02.015","DOIUrl":"10.1016/j.ijrefrig.2025.02.015","url":null,"abstract":"<div><div>With increasing global energy demand, improving the efficiency of refrigeration systems and reducing their environmental impact is crucial, especially since refrigeration often accounts for a significant portion of energy consumption. Traditional Proportional-Integral-Derivative (PID) control methods struggle with the complex, nonlinear nature of refrigeration systems, resulting in slow response times and limited optimization capabilities. While metaheuristic algorithms can perform global searches, they often lack the real-time fine-tuning necessary for optimal dynamic control. This study introduces Dynamic Synergy Optimization (DSO), a novel framework that integrates metaheuristic algorithms with PID control. Unlike conventional methods that only turn PID parameters using metaheuristics, DSO combines the global optimization power of metaheuristics with the real-time adjustment capabilities of PID, providing effective global search and local refinement. The PID controller ensures quick adaptation and system stability. Experimental results show that the Harris Hawks Optimization algorithm integrated with PID control outperforms standard PID control with a 63.3 % reduction in response time, a 69.2 % decrease in stabilization time, and a 19.65 % enhancement in energy efficiency. The DSO strategy significantly enhances the dynamic response and stability of refrigeration systems, reduces hysteresis, and accelerates the attainment of steady-state operation.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"173 ","pages":"Pages 100-110"},"PeriodicalIF":3.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143438189","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}

引用次数: 0

Research of CO2 high temperature heat pump for industrial steam generation with data center heat source

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-13 DOI: 10.1016/j.ijrefrig.2025.02.014

Junbin Chen, Cong Guo , Chunyu Feng, Xiao Qu, Sicong Tan, Yuyan Jiang

{"title":"Research of CO2 high temperature heat pump for industrial steam generation with data center heat source","authors":"Junbin Chen, Cong Guo , Chunyu Feng, Xiao Qu, Sicong Tan, Yuyan Jiang","doi":"10.1016/j.ijrefrig.2025.02.014","DOIUrl":"10.1016/j.ijrefrig.2025.02.014","url":null,"abstract":"<div><div>The solution of integrating large-scale high-temperature heat pump (HTHP) with data center not only reduces carbon emissions but also enhances energy efficiency, aligning with dual-carbon goals. However, pressure ratios and environmentally friendly refrigerants limit the conventional HTHPs. Therefore, this paper proposes an improved transcritical CO<sub>2</sub> HTHP steam system (CO<sub>2</sub>-NC) with dual-pressure gas coolers and expander. Detailed thermodynamic analysis, exergy analysis, and economic analysis are conducted to evaluate the cycle performance. Compared to the conventional CO<sub>2</sub> cycle, the COP of CO<sub>2</sub>-NC is improved by 32.7 %, and the pressure ratio is reduced by 13.22 %, with a 110 °C saturated steam supply. With the superior thermal matching performance of dual-pressure gas coolers, the irreversible loss of gas coolers in CO<sub>2</sub>-NC is diminished by 75.89 %. The total pressure ratio of CO<sub>2</sub>-NC is less than 1/4 of that in the conventional cycles with HFC/HFO refrigerants, providing an advantage in large-scale HTHPs with centrifugal compressors. Exergy analysis highlights that the expander in the CO<sub>2</sub>-NC decreases irreversible losses in the expansion process by 81.27 %. CO<sub>2</sub>-NC with the least variation in COP and pressure ratio shows excellent adaptability to data center heat sources, and CO<sub>2</sub>-NC exhibits the least variation with changes in saturated steam temperature. Furthermore, the optimum compressor discharge pressure for CO<sub>2</sub> HTHPs is analyzed. Economic analysis highlights the advantages of CO<sub>2</sub>-NC in operation and refrigerant costs with the constraints of high initial capital costs. This study emphasizes the potential of combining transcritical CO<sub>2</sub> HTHP to fulfill data center cooling and industrial heating needs.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"173 ","pages":"Pages 185-200"},"PeriodicalIF":3.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464623","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}

引用次数: 0

Experimental assessment of two-phase nozzle performance for low-GWP refrigerants

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2025-02-12 DOI: 10.1016/j.ijrefrig.2025.02.008

Paweł Jakończuk, Kamil Śmierciew, Adam Dudar, Jerzy Gagan, Dariusz Butrymowicz

{"title":"Experimental assessment of two-phase nozzle performance for low-GWP refrigerants","authors":"Paweł Jakończuk, Kamil Śmierciew, Adam Dudar, Jerzy Gagan, Dariusz Butrymowicz","doi":"10.1016/j.ijrefrig.2025.02.008","DOIUrl":"10.1016/j.ijrefrig.2025.02.008","url":null,"abstract":"<div><div>The performance of two-phase ejectors critically depends on the efficiency of motive nozzles, which govern the critical mass flow rate and overall system operation. However, accurately predicting nozzle performance under two-phase flow conditions remains challenging due to the complex interplay of thermodynamic and flow dynamics. This study addresses this issue by evaluating the performance coefficient of motive nozzles for three refrigerants: CO<sub>2</sub>, R600a, and R1234ze(E). Beyond ejector applications, understanding two-phase flow dynamics is essential for optimizing other key components, such as control valves and safety valves, which operate under similar conditions. Experiments conducted on a versatile test bench revealed significant differences in nozzle performance among the refrigerants. The performance coefficient ranged from 0.85 to 1.35 for CO<sub>2</sub>, 0.90 to 1.15 for R600a, and 0.92 to 1.22 for R1234ze(E). The Henry-Fauske model, used to predict critical mass flow, demonstrated an average deviation of 30 % for CO<sub>2</sub>, while deviations were much lower for R600a (9 %) and R1234ze(E) (4 %). The results highlight the sensitivity of the performance coefficient to the refrigerant thermodynamic properties, with CO<sub>2</sub> exhibiting the most complex flow behavior due to its lower critical temperature and higher compressibility. This study provides quantitative insights into the performance of motive nozzles under two-phase flow and validates the applicability of simplified models for predicting critical flow rates. The findings contribute to optimizing ejector and valve design, emphasizing the need for further validation with additional refrigerants to enhance model universality.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"173 ","pages":"Pages 111-122"},"PeriodicalIF":3.5,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445764","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}

引用次数: 0