International Journal of Refrigeration-revue Internationale Du Froid最新文献

{"title":"Effects of sensor measurement error on fault detection and diagnosis model for data center composite cooling system","authors":"Yiqi Zhang ,&nbsp;Baoqi Qiu ,&nbsp;Zongwei Han","doi":"10.1016/j.ijrefrig.2025.04.008","DOIUrl":"10.1016/j.ijrefrig.2025.04.008","url":null,"abstract":"<div><div>Fault detection and diagnosis (FDD) model for the cooling system is beneficial in elevating the reliability of data centers. Nevertheless, the model accuracy could be degraded by sensor measurement error, which may arise due to environmental interferences or inadequate maintenance practices. In the study, the impacts of sensor measurement error on the convolutional neuron network (CNN) based FDD model for the data center composite cooling system are assessed. Additionally, the coupled effects of sensor error and system control strategies on the FDD model are investigated. The results indicate that in vapor compression mode, a negative fixed sensor error of 1 K leads to an average 5 % greater decline in the CNN model accuracy compared to a positive error of the same magnitude. In contrast, the positive fixed error causes a 6.5 % higher decrease in heat pipe mode. Additionally, sensor errors have a negligible impact on model accuracy until exceeding the threshold, and the threshold of fixed error is 0.2 K in CNN model. Further, as a key control strategy involved parameters, the evaporating temperature error is critical to FDD model accuracy. In the fixed bias conditions, when the error magnitude is 1 K, the accuracy of FDD model decreases within the range of 24.8 % to 45.1 %.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 245-258"},"PeriodicalIF":3.5,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845111","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":"Parameters correlation and sensitivity analyses for single-segment inertance tubes in pulse tube cryocoolers: a comprehensive large-scale dataset investigation","authors":"Hao Chen,&nbsp;Shanshan Li,&nbsp;Ziyang Wang","doi":"10.1016/j.ijrefrig.2025.04.006","DOIUrl":"10.1016/j.ijrefrig.2025.04.006","url":null,"abstract":"<div><div>The inertance tube, as a crucial component of pulse tube refrigerators, directly determines the refrigeration efficiency through its phase-shifting capability. Traditional design methods for inertance tubes are often inefficient and struggle to identify the optimal dimensions due to the multiple influencing parameters and their complex coupling relationships. To address these issues, a comprehensive dataset of 641,986 data points, encompassing the phase-shifting characteristics of single-segment inertance tubes across a range of operational parameters and structural dimensions, was compiled to enhance precision. Principal Component Analysis was then employed to conduct an in-depth analysis of the correlations between the phase-shifting capability of the inertance tube and its operating and structural parameters. Additionally, Local Sensitivity Analysis was performed to evaluate the sensitivity of structural parameters at various value points. Combining the results of correlation and sensitivity analyses, an innovative design process and parameter selection strategy for inertance tube design was proposed, aiming to offer targeted guidance and improve the design efficiency.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 314-333"},"PeriodicalIF":3.5,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850363","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":"A comprehensive analysis of capacitive signals of two-phase R134a characteristics in a microchannel heat exchanger header with and without a distributor","authors":"Jiajia Song ,&nbsp;Hequn Liu ,&nbsp;Shenghan Jin ,&nbsp;Chao Yuan ,&nbsp;Jinqing Peng ,&nbsp;Houpei Li","doi":"10.1016/j.ijrefrig.2025.04.005","DOIUrl":"10.1016/j.ijrefrig.2025.04.005","url":null,"abstract":"<div><div>The maldistribution of refrigerant in header has a serious impact on the performance of the microchannel heat exchanger (MCHX). This study investigated using to obtain an improved flow distribution distributor in a MCHX. The tested inlet vapor quality covered from 0.2 to 0.6. Mass flow rate was 10 g/s. In the heat exchanger header, the two-phase distribution was quantified using a capacitance sensor for with and without distributor cases. The capacitive signals were comprehensively analyzed in the time, amplitude and frequency domains. Probability density function (PDF) and Fast Fourier Transform (FFT) of the capacitive signals were used to characterize flow patterns. The local vapor qualities calculated by the correlation was used to quantify two-phase distribution. This comprehensive analysis improved the accuracy of capacitive signal processing of two-phase flow characteristics. In the Fast Fourier Transform of capacitive signals, the more violent the two-phase flow, the greater fluctuation on the amplitude. The improvement of two-phase distribution by distributor and the two-phase flow characteristics at the distribution hole were discussed. At low inlet vapor quality<span><math><mrow><mo>(</mo><mrow><msub><mi>x</mi><mrow><mi>i</mi><mi>n</mi></mrow></msub><mo>≤</mo><mn>0.3</mn></mrow><mo>)</mo></mrow></math></span>, the distributor had a better effect on the maldistribution. At high inlet vapor quality<span><math><mrow><mo>(</mo><mrow><msub><mi>x</mi><mrow><mi>i</mi><mi>n</mi></mrow></msub><mo>=</mo><mn>0.6</mn></mrow><mo>)</mo></mrow></math></span>, alternate vapor-liquid distribution would occur at the distribution hole. In this paper, the capacitive signals were comprehensively analyzed in the time, amplitude and frequency domains in the MCHX header for the first time. The two-phase flow state was specifically evaluated through the capacitive signal characteristics.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 358-372"},"PeriodicalIF":3.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860648","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":"Comparative study on adaptable intelligent frost recognition method for air-source heat pump and cold chain based on image texture features under complex lighting conditions","authors":"Yingjie Xu ,&nbsp;Hengrui Zhang ,&nbsp;Kai Wu ,&nbsp;Huaqiang Jin ,&nbsp;Mengjie Song ,&nbsp;Xi Shen","doi":"10.1016/j.ijrefrig.2025.03.047","DOIUrl":"10.1016/j.ijrefrig.2025.03.047","url":null,"abstract":"<div><div>The energy efficiency enhancement of refrigeration/heat pump systems is a crucial aspect of carbon emissions reduction. Accurately recognizing the frosting state of their evaporators in low-temperature environments to achieve precise defrosting is key to reducing system energy consumption. Intelligent recognition methods based on evaporator images hold promise for high recognition rates. However, in practical conditions, light intensity can severely reduce the identification accuracy of existing methods, necessitating improvements. Therefore, a highly adaptable new method based on texture features of evaporator surface images is presented in this study, where texture features is extracted by minimum-redundancy-maximum-relevance-enhanced gray level co-occurrence matrix, and classified by sparrow-algorithm-optimized extreme learning machine (GLCM-SELM), to overcome the impact of various light intensity. This method is validated using a dataset of 4125 evaporator images of three frosting states, which is experimentally collected under light intensity ranging from 5 to 2370 lx. Performance study and comparative analysis against existing methods are carried out. Results indicate that the new method achieves identification accuracy of approximately 95 % across different conditions, significantly outperforming existing methods by 6 % to 35 %. Its remarkably smaller standard deviation (0.05) demonstrates high stability. It also shows fast computing speed and low cost. Generally, it has good application potential.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 273-287"},"PeriodicalIF":3.5,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143848014","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 and theoretical study on the optimal placement of reflective shield in multilayer insulation systems","authors":"Abdul Rehman Hashmi ,&nbsp;Haoren Wang ,&nbsp;Ruyi Ji ,&nbsp;Bo Wang ,&nbsp;Anas A. Rahman ,&nbsp;Fatima Saadat ,&nbsp;Yunfei Gao ,&nbsp;Zhihua Gan","doi":"10.1016/j.ijrefrig.2025.04.004","DOIUrl":"10.1016/j.ijrefrig.2025.04.004","url":null,"abstract":"<div><div>Multilayer insulation (MLI) systems are widely used in cryogenic applications to minimize heat leak. Despite advancements in research work regarding the optimization of different MLI configurations, there is still a lack of appropriate structural design. The reflective shield will improve the performance of MLI by reducing thermal radiation. This study aims to improve the thermal performance of MLI systems by incorporating reflective shields with MLI materials. More specific, it is focused on determining the optimal placement of reflective shields within the MLI structure to achieve a minimum heat leak. A modified layer-by-layer model has been established to predict the thermal performance obtained from using single and double reflective shield placements. Such predictions were validated through experiments using a liquid nitrogen boil-off calorimeter. The obtained results demonstrate that placing a single reflective shield at the warm boundary improves thermal performance by 18 % compared to using MLI solely, emphasizing the relevance of reflective shield-MLI combinations in cryogenic applications. This work is conducive to offering potential applications for cryogenic clean fuel storage and transportation.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 196-209"},"PeriodicalIF":3.5,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816052","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":"Performance investigations on nonflammable CO2/HFOs mixtures for an air-source heat pump water heater during wintertime","authors":"Kaiyin Yang ,&nbsp;Zhen Zhao ,&nbsp;Yilun Liu ,&nbsp;Qin Wang ,&nbsp;Long Jiang ,&nbsp;Ziqian Xue ,&nbsp;Jielin Luo","doi":"10.1016/j.ijrefrig.2025.03.044","DOIUrl":"10.1016/j.ijrefrig.2025.03.044","url":null,"abstract":"<div><div>With heating demand in buildings on the rise, air-source heat pumps (ASHPs) offer a vital, low-emission alternative to traditional methods. In cold regions, ASHP faces application resistances like combustion and system complexity. These can be mitigated using zeotropic mixtures with hydrofluoroolefins (HFOs). However, the role of ternary mixtures in enhancing performance and safety remains underexplored. This study proposes novel mixtures of CO₂ and HFOs in a simple recuperative configuration. Within the nonflammable range, the optimal ternary mixture CO₂/R1234ze(E)/R1336mzz(E), shows up to 35.8 % improvement in the coefficient of performance (COP) compared to binary mixtures. Up to 14.3 % enhancement in COP versus a traditional ASHP system is achieved, resulting in an annual performance boost of 7.0 % in cold climates. Exergy analysis indicates the low irreversible losses in throttling and condensing are the main contributors to the improvement. A life cycle assessment reveals both economic and environmental advantages, with reductions in costs and emissions of up to 10.7 % and 25.5 %, respectively. Sensitivity analysis indicates that easily adjustable operating pressures significantly impact COP, but the optimal mixture still maintains high efficiency despite variations. Ternary mixtures also show comparable COP to ASHP using CO₂, with significant discharge pressure reductions. The proposed mixtures enhance safety, energy efficiency, and system simplicity, supporting the global adoption of ASHP for energy savings and emission reductions, thus advancing carbon neutrality efforts.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 389-399"},"PeriodicalIF":3.5,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143870679","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":"Innovative photoacoustic instrument for fast and accurate detection and localization of R-134a leaks in refrigeration systems","authors":"Panna Végh ,&nbsp;Bence Molnár ,&nbsp;Máté Molnár ,&nbsp;Piroska Ailer ,&nbsp;Zoltán Bozóki ,&nbsp;Helga Huszár","doi":"10.1016/j.ijrefrig.2025.04.003","DOIUrl":"10.1016/j.ijrefrig.2025.04.003","url":null,"abstract":"<div><div>Refrigerant leaks are a common issue that can seriously impact both the performance of refrigeration systems and the environment. The need for reliable and sensitive leak detection has become increasingly critical due to regulatory bans on refrigerants with a high global warming potential. A new potential option for detecting possible leaks in refrigeration installations is the development of a highly sensitive photoacoustic (PA) instrument, which allows for more accurate, faster and easier detection of leakage points in refrigeration equipment than currently commercially available equipment. This article reports on the development of a highly sensitive photoacoustic instrument for the detection and localization of R-134a leaks to identify leaks at rates as low as 1.2 g/year in refrigeration systems. The developed system includes a quantum cascade laser that operates around 10.3 µm with a maximum output power of 84 mW. It features a stainless steel photoacoustic cell with two 40 mm resonator tubes, each with a 3.5 mm inner diameter. This setup ensures the accurate detection of R-134a refrigerant leaks by targeting specific absorption lines. The fast response time, wide dynamic concentration range, and high sensitivity of the PA instrument make it a promising tool for refrigerant leak detection. The paper also discusses spectral interference from other environmental and refrigerant gases, such as water vapor, carbon dioxide, ammonia, methane, propane, and R-32. A detailed finite element model has been developed and implemented in COMSOL Multiphysics 6.2. The simulation results matched the experimental data, validating the accuracy of the PA system.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 164-173"},"PeriodicalIF":3.5,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799920","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":"Ammonia two-phase flow through the horizontal and inclined impacting T-junctions","authors":"Vasyl Ruzaikin,&nbsp;Ivan Lukashov,&nbsp;Andrii Breus","doi":"10.1016/j.ijrefrig.2025.04.001","DOIUrl":"10.1016/j.ijrefrig.2025.04.001","url":null,"abstract":"<div><div>The two-phase ammonia flow through the horizontal and inclined impacting T-junctions has been experimentally studied. The phase separation has been investigated in the ID 4, 6 and 10 mm T-junctions at different saturation temperatures (30 to 65 °C), vapour qualities (0.1 to 0.7) and mass fluxes (50 to 300 kg·m^-2s^-1). Two separation patterns in the horizontal impacting T-junctions were observed. The first one, vapour momentum-independent, shows weak sensitivity of the phase separation behaviour on the pressure, inlet vapour quality and mass velocity. The second one, vapour momentum-dependent, is characterised by the region with the equal phase distribution between the T-junction outlets. The transition between the phase separation patterns does not depend on the inlet two-phase flow pattern. A straightforward phenomenological model was proposed for the separation pattern identification and the evaluation of the vapour quality in the outlet branch of the horizontal impacting T-junctions with a feasible accuracy of ±20 %. Downward orientation (-45°, -90°) of the T-junction inlet leads to a higher phase maldistribution between the outlets than the upward and horizontal configuration. The effect degrades with the mass velocity increase and diameter reduction. The inclination of the T-junction outlets regarding the horizontal plane enhances the phase separation, with the vapour-rich mixture going to the top outlet. The effect intensifies with the increase in the inclination angle and the decrease in the T-junction mass flow rate ratio.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 235-244"},"PeriodicalIF":3.5,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845110","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":"Thermodynamic analysis and optimization of an ejector refrigeration system for sustainable cooling applications","authors":"Nawel Khaldi,&nbsp;Safa Sdiri,&nbsp;Mariem Lazaar","doi":"10.1016/j.ijrefrig.2025.03.004","DOIUrl":"10.1016/j.ijrefrig.2025.03.004","url":null,"abstract":"<div><div>Leveraging low-grade waste heat as an energy source has gained significant interest in recent years. Among the promising technologies for this purpose, heat-driven ejector refrigeration systems have emerged as potential solutions for industrial and commercial cooling applications. While these systems hold significant potential, their widespread adoption has been hindered by relatively low coefficients of performance (COP) and the use of environmentally harmful refrigerants.</div><div>This study aims to investigate and optimize ejector refrigeration systems to enhance energy efficiency and ensure sustainable cooling solutions. It involves evaluating the influence of operating parameters and refrigerant selection on system performance, modeled using the Engineering Equation Solver (EES). A comparative analysis of the refrigerants R134a and the environmentally friendly R1234yf is conducted, focusing on key parameters to identify optimal system conditions. Our findings reveal that condensation and evaporation temperatures are crucial factors influencing system performance. While both R134a and R1234yf exhibit similar trends, R1234yf demonstrates superior entrainment ratios under specific operating conditions, making it a promising alternative for sustainable refrigeration systems.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"174 ","pages":"Pages 372-387"},"PeriodicalIF":3.5,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738919","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":"Study of optimizing the secondary cylinder size in a novel dual-piston carbon dioxide linear compressor to suppress piston offset","authors":"Fanchen Kong ,&nbsp;Shanquan Liu ,&nbsp;Fang Wang ,&nbsp;Shuo Zhang ,&nbsp;Guifang Wu ,&nbsp;Zhouhang Hu ,&nbsp;Mingsheng Tang ,&nbsp;Huiming Zou ,&nbsp;Changqing Tian","doi":"10.1016/j.ijrefrig.2025.03.046","DOIUrl":"10.1016/j.ijrefrig.2025.03.046","url":null,"abstract":"<div><div>Based on a previously proposed novel dual-piston two-stage carbon dioxide (CO₂) linear compressor, this research aims to further inhibit the piston offset and improve overall system performance and efficiency by purposefully exploring the optimal design of the two-stage cylinder diameter. A comprehensive simulation model is developed to analyse the dynamic characteristics and performance implications associated with varying cylinder diameters in the two-stage configuration. The study explores the influence of cylinder diameter on gas forces, piston offset, and compression process leakage. The results show that through the optimized design of the two-stage cylinder diameter, the piston offset can be reduced by &gt;50 % and the relative leakage loss can be reduced by 2.22 %. Under 12 MPa discharge pressure, a relative efficiency improvement of 5.27 % can be achieved. The optimal compressor efficiency is achieved between intermediate pressure index 4 and 5. This result provides valuable guidance for the design of the second-stage piston. Finally, a prototype was developed according to the design principle, and its piston offset suppression effect was validated experimentally. Under a pressure difference close to 0.7 MPa, the piston offset consistently remained below 0.2 mm.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"175 ","pages":"Pages 146-155"},"PeriodicalIF":3.5,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785134","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}