International Journal of Refrigeration-revue Internationale Du Froid最新文献_第7页

CFD analysis of an evaporator in diffusion absorption refrigeration systems using helium as an auxiliary gas 以氦为辅助气体的扩散吸收式制冷系统蒸发器的CFD分析

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-03-01 Epub Date: 2026-01-03 DOI: 10.1016/j.ijrefrig.2026.01.003

S. Zebbar, D. Zebbar, Z. Rahmani

This paper details a computational fluid dynamics (CFD) simulation applied to the evaporator of a diffusion absorption refrigeration (DAR) system, using a water-ammonia mixture as the working fluid and helium as an auxiliary gas. Although hydrogen is traditionally preferred in DAR systems due to its favorable properties for separation in the absorber and enhanced mass transfer, its high flammability imposes safety constraints. Therefore, to address these concerns and improve system efficiency, helium is considered a safer alternative, particularly for high-power units. Moreover, building on a previously validated numerical model of the evaporator in CONVERGE CFD with the Reynolds-Averaged Navier-Stokes (RANS) approach, this study investigates the evaporator’s behavior across operating pressures of 10–25 bar, aiming to determine the optimal pressure when helium is used as the auxiliary gas.

A series of simulations were performed for total pressure values ranging from 10 to 25 bar. The findings indicate that lower total pressures result in reduced evaporation temperatures across the evaporator, leading to improved evaporation and heat transfer efficiency. Notably, a total pressure of 10-12 bar is identified as optimal for maximizing cooling capacity when helium is used as the auxiliary gas in a water-ammonia DAR system. These findings underscore the potential of helium in solar-driven absorption–diffusion refrigeration systems, despite its scarcity and high cost, particularly under the limited thermal input characteristic of renewable sources. The results indicate that helium’s unique properties make it an attractive option for enhancing both safety and efficiency, with the DAR system performing noticeably better when operated with helium than with hydrogen.

以水-氨混合物为工作流体，氦气为辅助气体，对扩散吸收式制冷（DAR）系统蒸发器进行了计算流体力学（CFD）模拟。传统上，氢气是DAR系统的首选，因为它在吸收器中具有良好的分离性能和增强的传质性，但其高可燃性限制了安全性。因此，为了解决这些问题并提高系统效率，氦气被认为是一种更安全的替代品，特别是对于大功率装置。此外，基于先前在CONVERGE CFD中使用reynolds - average Navier-Stokes （RANS）方法验证的蒸发器数值模型，本研究研究了蒸发器在10-25 bar工作压力下的行为，旨在确定使用氦气作为辅助气体时的最佳压力。对10 ~ 25bar的总压力值进行了一系列模拟。研究结果表明，较低的总压力会降低蒸发器的蒸发温度，从而提高蒸发和传热效率。值得注意的是，当在水-氨雷达系统中使用氦气作为辅助气体时，总压力为10-12 bar被认为是冷却能力最大化的最佳选择。这些发现强调了氦在太阳能驱动的吸收-扩散制冷系统中的潜力，尽管其稀缺和高成本，特别是在可再生能源有限的热输入特性下。结果表明，氦气的独特性质使其成为提高安全性和效率的有吸引力的选择，在使用氦气时，DAR系统的性能明显优于使用氢气时。

{"title":"CFD analysis of an evaporator in diffusion absorption refrigeration systems using helium as an auxiliary gas","authors":"S. Zebbar, D. Zebbar, Z. Rahmani","doi":"10.1016/j.ijrefrig.2026.01.003","DOIUrl":"10.1016/j.ijrefrig.2026.01.003","url":null,"abstract":"<div><div>This paper details a computational fluid dynamics (CFD) simulation applied to the evaporator of a diffusion absorption refrigeration (DAR) system, using a water-ammonia mixture as the working fluid and helium as an auxiliary gas. Although hydrogen is traditionally preferred in DAR systems due to its favorable properties for separation in the absorber and enhanced mass transfer, its high flammability imposes safety constraints. Therefore, to address these concerns and improve system efficiency, helium is considered a safer alternative, particularly for high-power units. Moreover, building on a previously validated numerical model of the evaporator in CONVERGE CFD with the Reynolds-Averaged Navier-Stokes (RANS) approach, this study investigates the evaporator’s behavior across operating pressures of 10–25 bar, aiming to determine the optimal pressure when helium is used as the auxiliary gas.</div><div>A series of simulations were performed for total pressure values ranging from 10 to 25 bar. The findings indicate that lower total pressures result in reduced evaporation temperatures across the evaporator, leading to improved evaporation and heat transfer efficiency. Notably, a total pressure of 10-12 bar is identified as optimal for maximizing cooling capacity when helium is used as the auxiliary gas in a water-ammonia DAR system. These findings underscore the potential of helium in solar-driven absorption–diffusion refrigeration systems, despite its scarcity and high cost, particularly under the limited thermal input characteristic of renewable sources. The results indicate that helium’s unique properties make it an attractive option for enhancing both safety and efficiency, with the DAR system performing noticeably better when operated with helium than with hydrogen.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"183 ","pages":"Pages 95-107"},"PeriodicalIF":3.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923293","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

Corrigendum to ‘Numerical and experimental evaluation of the thermal and dynamic performance of a phase change material in an indirect solar dryer’ International Journal of Refrigeration 174 (2025) 98–110 “间接太阳能干燥器中相变材料热和动态性能的数值和实验评估”国际制冷杂志174(2025)98-110的勘误表

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-03-01 Epub Date: 2026-01-02 DOI: 10.1016/j.ijrefrig.2025.12.037

Dounia Chaatouf , Mourad Salhi , Abir Bria , Benyounes Raillani , Samir Amraqui , Ahmed Mezrhab

引用次数: 0

Dynamic performance analysis of an ejector refrigeration system with a direct-expansion solar generator 直接膨胀式太阳能发电机组喷射器制冷系统动态性能分析

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-03-01 Epub Date: 2025-12-30 DOI: 10.1016/j.ijrefrig.2025.12.025

Santiago Valencia-Cañola , Federico Méndez , Carlos A. Bustamante

Ejector Refrigeration Systems (ERS) can obtain their primary energy source from renewable sources such as solar radiation, which transfers heat to the ERS generator to achieve optimal operation. Direct-expansion solar collectors have been gain attention in systems such as solar heat pumps, avoiding the use of additional subsystems and energy sources and reducing costs and electricity consumption. In this study, the dynamic performance of an ERS with direct-expansion solar generator is assessed by means of a validated mathematical model that couples ERS subsystem operation. The proposed model predicts the global behavior of the cycle by describing mass, momentum and energy transport in each subsystem and by coupling their inlet and outlet conditions. An ERS basic design for average meteorological condition with direct-expansion solar generator is numerically analyzed for different transient operating conditions, in terms of solar radiation and ambient temperature, obtained from the typical meteorological year (TMY) of Mexico City. The results show that in favorable environmental conditions, the system can operate 2.3 h longer than the average day because the generator can maintain the refrigerant vapor phase for a longer period. However, refrigerant overheating increases, causing a reduction in the entrainment ratio (ER) and coefficient of performance (COP). This study shows that the ERS with a direct-expansion solar generator can operate for more than 90% of the TMY, reaching ER values of up to 0.6 and COP of up to 0.5, which are close to conventional ERS.

弹射式制冷系统（ERS）可以从可再生能源（如太阳辐射）中获得主要能源，将热量传递给ERS发电机以实现最佳运行。在太阳能热泵等系统中，直接膨胀式太阳能收集器已得到注意，避免使用额外的子系统和能源，并减少费用和电力消耗。本研究通过验证的耦合ERS子系统运行的数学模型，对带有直扩式太阳能发电机组的ERS进行了动态性能评估。提出的模型通过描述每个子系统的质量、动量和能量输运以及它们的入口和出口条件的耦合来预测循环的整体行为。根据墨西哥城典型气象年（TMY）的太阳辐射和环境温度，对平均气象条件下带直扩式太阳能发电机的ERS基本设计进行了数值分析。结果表明，在良好的环境条件下，由于发电机能延长制冷剂气相的维持时间，系统的运行时间比平均每天长2.3 h。但是，制冷剂过热会增加，导致夹带比（ER）和性能系数（COP）降低。本研究表明，带直扩式太阳能发电机组的ERS可运行TMY的90%以上，ER值可达0.6，COP值可达0.5，接近常规ERS。

{"title":"Dynamic performance analysis of an ejector refrigeration system with a direct-expansion solar generator","authors":"Santiago Valencia-Cañola , Federico Méndez , Carlos A. Bustamante","doi":"10.1016/j.ijrefrig.2025.12.025","DOIUrl":"10.1016/j.ijrefrig.2025.12.025","url":null,"abstract":"<div><div>Ejector Refrigeration Systems (ERS) can obtain their primary energy source from renewable sources such as solar radiation, which transfers heat to the ERS generator to achieve optimal operation. Direct-expansion solar collectors have been gain attention in systems such as solar heat pumps, avoiding the use of additional subsystems and energy sources and reducing costs and electricity consumption. In this study, the dynamic performance of an ERS with direct-expansion solar generator is assessed by means of a validated mathematical model that couples ERS subsystem operation. The proposed model predicts the global behavior of the cycle by describing mass, momentum and energy transport in each subsystem and by coupling their inlet and outlet conditions. An ERS basic design for average meteorological condition with direct-expansion solar generator is numerically analyzed for different transient operating conditions, in terms of solar radiation and ambient temperature, obtained from the typical meteorological year (TMY) of Mexico City. The results show that in favorable environmental conditions, the system can operate 2.3 h longer than the average day because the generator can maintain the refrigerant vapor phase for a longer period. However, refrigerant overheating increases, causing a reduction in the entrainment ratio (ER) and coefficient of performance (COP). This study shows that the ERS with a direct-expansion solar generator can operate for more than 90% of the TMY, reaching ER values of up to 0.6 and COP of up to 0.5, which are close to conventional ERS.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"183 ","pages":"Pages 1-14"},"PeriodicalIF":3.8,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883288","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 and general correlation of condensation heat transfer for zeotropic mixture refrigerants in smooth and microfin tubes 共沸混合制冷剂在光滑和微翅片管内冷凝换热的实验研究及一般关联

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.ijrefrig.2025.11.025

Hakimatul Ubudiyah , Afdhal Kurniawan Mainil , Akio Miyara

This study investigated the condensation heat transfer of R32/R1234yf mixtures in smooth and microfin tubes with outer diameters of 5.0 and 3.5 mm, respectively. The experiments were conducted at mass velocities of 50, 100, and 200 kg m^-2 s^-1 and saturation temperatures of 20°C. The effect of mass velocity, vapor quality, and mass fraction on heat transfer was evaluated. For the smooth tube, R32/R1234yf mixture with mass ratio of 21.5/78.5 has lower heat transfer than pure R1234yf in all mass velocities due to the heat transfer degradation phenomenon. For the microfin tube, R32/R1234yf with mass ratio of 68.9/31.1 has higher heat transfer compared to R1234yf, but cannot exceed the heat transfer of R32. Meanwhile, the mixture R32/R1234yf with mass ratio of 21.5/78.5 has less heat transfer than pure R1234yf for mass velocities of 50 and 100 kg m^-2 s^-1. However, at a low vapor quality and a mass velocity of 200 kg m^-2 s^-1, the heat transfer is almost the same as that of R1234yf due to less heat transfer degradation. The new correlations were developed by adding the heat transfer degradation effect to the Nusselt number for forced and natural convection. The correlation developed to predict condensation of mixture refrigerants for smooth tubes can be applied to tubes with inner diameters between 4 and 8.4 mm. It can predict both the present experimental data and other researchers' data with mean deviation of 16.4%. Meanwhile, the correlation developed to predict the condensation of mixture refrigerants for microfin tubes can be applied to tubes with inner diameters ranging from 2.5 to 8.9 mm, and it can predict current experimental data and data from other researchers with an average deviation of 19.8%.

研究了R32/R1234yf混合物在外径分别为5.0 mm和3.5 mm的光滑管和微鳍管内的冷凝换热特性。实验的质量速度分别为50、100和200 kg m-2 s-1，饱和温度为20℃。评价了质量速度、蒸汽质量和质量分数对传热的影响。对于光滑管，由于传热退化现象，质量比为21.5/78.5的R32/R1234yf混合物在各质量速度下的换热均低于纯R1234yf。对于微鳍管，质量比为68.9/31.1的R32/R1234yf的换热系数高于R1234yf，但不能超过R32的换热系数。同时，质量比为21.5/78.5的R32/R1234yf混合物在质量速度为50和100 kg m-2 s-1时的换热量小于纯R1234yf。然而，在低蒸汽质量和质量速度为200 kg m-2 s-1时，由于传热退化较小，传热与R1234yf几乎相同。通过在强迫对流和自然对流的努塞尔数中加入传热退化效应，建立了新的关联。用于预测光滑管中混合制冷剂冷凝的相关性可以应用于内径在4到8.4 mm之间的管。它既可以预测现有的实验数据，也可以预测其他研究者的数据，平均偏差为16.4%。同时，用于预测微翅管混合制冷剂冷凝的相关关系适用于内径为2.5 ~ 8.9 mm的管道，预测当前实验数据与其他研究数据的平均偏差为19.8%。

{"title":"Experimental study and general correlation of condensation heat transfer for zeotropic mixture refrigerants in smooth and microfin tubes","authors":"Hakimatul Ubudiyah , Afdhal Kurniawan Mainil , Akio Miyara","doi":"10.1016/j.ijrefrig.2025.11.025","DOIUrl":"10.1016/j.ijrefrig.2025.11.025","url":null,"abstract":"<div><div>This study investigated the condensation heat transfer of R32/R1234yf mixtures in smooth and microfin tubes with outer diameters of 5.0 and 3.5 mm, respectively. The experiments were conducted at mass velocities of 50, 100, and 200 kg m<sup>-2</sup> s<sup>-1</sup> and saturation temperatures of 20°C. The effect of mass velocity, vapor quality, and mass fraction on heat transfer was evaluated. For the smooth tube, R32/R1234yf mixture with mass ratio of 21.5/78.5 has lower heat transfer than pure R1234yf in all mass velocities due to the heat transfer degradation phenomenon. For the microfin tube, R32/R1234yf with mass ratio of 68.9/31.1 has higher heat transfer compared to R1234yf, but cannot exceed the heat transfer of R32. Meanwhile, the mixture R32/R1234yf with mass ratio of 21.5/78.5 has less heat transfer than pure R1234yf for mass velocities of 50 and 100 kg m<sup>-2</sup> s<sup>-1</sup>. However, at a low vapor quality and a mass velocity of 200 kg m<sup>-2</sup> s<sup>-1</sup>, the heat transfer is almost the same as that of R1234yf due to less heat transfer degradation. The new correlations were developed by adding the heat transfer degradation effect to the Nusselt number for forced and natural convection. The correlation developed to predict condensation of mixture refrigerants for smooth tubes can be applied to tubes with inner diameters between 4 and 8.4 mm. It can predict both the present experimental data and other researchers' data with mean deviation of 16.4%. Meanwhile, the correlation developed to predict the condensation of mixture refrigerants for microfin tubes can be applied to tubes with inner diameters ranging from 2.5 to 8.9 mm, and it can predict current experimental data and data from other researchers with an average deviation of 19.8%.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 147-158"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145682300","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

Performance optimization in thermoelectric coolers using physical data-driven artificial neural networks 利用物理数据驱动的人工神经网络优化热电冷却器的性能

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.ijrefrig.2025.11.023

Somaya Salamah , Candeniz Seckin , Süha Tuna

Driven by industrial growth and the demand for clean energy, thermoelectric coolers (TECs) have emerged as a sustainable, pollution-free cooling solution; however, their widespread adoption remains limited by low coefficient of performance (COP) under varying thermal and electrical conditions. This study presents a deep learning framework based on artificial neural networks (ANNs) developed in MATLAB to predict TEC performance across diverse operating scenarios. A dataset of 40,000 samples was generated from fundamental physical equations with optimized electrical current values obtained via an iterative gradient descent, ensuring adherence to the thermoelectric nonlinearities and energy conservation. The ANN architecture comprises one input layer, 15 hidden layers with Leaky Rectified Linear Unit (ReLU) activation, and one output layer, trained using the Root Mean Square Error (RMSE) as the loss function. To enhance predictive accuracy, a Genetic Algorithm (GA) was employed to optimize key geometric parameters-leg length, leg width, and fill factor. The optimized ANN-GA model achieved RMSE reduction of approximately 60 % under constant cold-side temperature (

T_{c}

) and 54 % under constant heat-flux (

Q_{c}^{˙}

) conditions, maintaining coefficient of determination (

R^{2}

) values above 0.95 for both COP and power density (PD) predictions. The strong agreement between predicted and actual results confirms the model’s robustness and accuracy. This study establishes a physics-informed, data-driven ANN-GA framework for reliable performance prediction and design optimization of TECs, providing a foundation for future advances in thermoelectric device development and sustainable cooling technologies.

在工业增长和清洁能源需求的推动下，热电冷却器（tec）已成为一种可持续的、无污染的冷却解决方案；然而，在不同的热和电条件下，它们的广泛采用仍然受到低性能系数（COP）的限制。本研究提出了一个基于MATLAB开发的人工神经网络（ann）的深度学习框架，用于预测TEC在不同操作场景下的性能。根据基本物理方程生成40,000个样本的数据集，并通过迭代梯度下降获得优化的电流值，确保遵守热电非线性和节能。人工神经网络架构包括一个输入层，15个具有泄漏整流线性单元（ReLU）激活的隐藏层，以及一个使用均方根误差（RMSE）作为损失函数进行训练的输出层。为了提高预测精度，采用遗传算法对腿长、腿宽和填充系数等关键几何参数进行优化。优化后的ANN-GA模型在恒定冷侧温度（Tc）条件下RMSE降低约60%，在恒定热通量（Qc˙）条件下RMSE降低约54%，COP和功率密度（PD）预测的决定系数（R2）均保持在0.95以上。预测结果与实际结果吻合较好，证实了模型的稳健性和准确性。本研究建立了一个物理信息、数据驱动的ANN-GA框架，用于tec的可靠性能预测和设计优化，为热电器件开发和可持续冷却技术的未来发展奠定了基础。

{"title":"Performance optimization in thermoelectric coolers using physical data-driven artificial neural networks","authors":"Somaya Salamah , Candeniz Seckin , Süha Tuna","doi":"10.1016/j.ijrefrig.2025.11.023","DOIUrl":"10.1016/j.ijrefrig.2025.11.023","url":null,"abstract":"<div><div>Driven by industrial growth and the demand for clean energy, thermoelectric coolers (TECs) have emerged as a sustainable, pollution-free cooling solution; however, their widespread adoption remains limited by low coefficient of performance (COP) under varying thermal and electrical conditions. This study presents a deep learning framework based on artificial neural networks (ANNs) developed in MATLAB to predict TEC performance across diverse operating scenarios. A dataset of 40,000 samples was generated from fundamental physical equations with optimized electrical current values obtained via an iterative gradient descent, ensuring adherence to the thermoelectric nonlinearities and energy conservation. The ANN architecture comprises one input layer, 15 hidden layers with Leaky Rectified Linear Unit (ReLU) activation, and one output layer, trained using the Root Mean Square Error (RMSE) as the loss function. To enhance predictive accuracy, a Genetic Algorithm (GA) was employed to optimize key geometric parameters-leg length, leg width, and fill factor. The optimized ANN-GA model achieved RMSE reduction of approximately 60 % under constant cold-side temperature (<span><math><msub><mi>T</mi><mi>c</mi></msub></math></span>) and 54 % under constant heat-flux (<span><math><munderover><mi>Q</mi><mi>c</mi><mi>˙</mi></munderover></math></span>) conditions, maintaining coefficient of determination (<span><math><msup><mi>R</mi><mn>2</mn></msup></math></span>) values above 0.95 for both COP and power density (PD) predictions. The strong agreement between predicted and actual results confirms the model’s robustness and accuracy. This study establishes a physics-informed, data-driven ANN-GA framework for reliable performance prediction and design optimization of TECs, providing a foundation for future advances in thermoelectric device development and sustainable cooling technologies.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 114-125"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145682239","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 on the motion characteristics of sliding vane in rolling piston compressor under low-speed condition 滚动活塞压缩机滑片在低速工况下的运动特性研究

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-12-19 DOI: 10.1016/j.ijrefrig.2025.12.021

Yanjun Du , Shunan Li , Jianhua Wu , Qingwen Liu , Zibo Zhao

The rolling rotor compressors frequently face operational challenges such as vane impact noise and impaired efficiency under low-speed conditions, which hinder the ability to meet the growing demand for energy-efficient and comfortable air conditioning systems. It is essential to investigate the lubrication and motion characteristics of the vane side in rolling rotor compressors for room air conditioners under low-speed conditions, in order to ensure compressor performance and system comfort during low-speed operation. This paper conducted the force analysis based on the finite element discretization of the oil film area on the vane side. Experiments were conducted to measure the temperature, pressure, and cooling capacity at multiple points in the air conditioning system under different operating conditions by modifying the air conditioning system and rolling rotor compressor. Meanwhile, noise collection equipment was used to measure the system noise at the back of the vane and in its vertical direction, and the noise spectrum was analyzed. The results show that the maximum inclination angle of the vane decreases by 14.2 % at low-speed conditions, the range of inclination angle variation shrinks by 52.4 %, and the secondary motion of the vane weakens, compared to the rated cooling condition. Furthermore, the detachment of the vane at low-speed was calculated and compared with the experimental results of noise spectrum, verifying the rationality of the mathematical model in this paper. The calculation and experimental results of vane detachment show that after the vane detaches from the rolling rotor, the compressor volumetric efficiency drops below 80 %, and impact noise is generated, which has a significant impact on the noise variation at the back of the vane. The decrease in longitudinal gas force and poor lubrication condition on the vane side at low-speed are the main reasons for the vane detaching before the 180° rotation angle.

滚动转子压缩机经常面临运行挑战，如叶片冲击噪声和低速条件下的效率下降，这阻碍了满足日益增长的节能和舒适空调系统需求的能力。研究室内空调滚动转子压缩机叶片侧在低速工况下的润滑和运动特性，对于保证压缩机的低速运行性能和系统的舒适性是十分必要的。本文对叶片侧油膜区域进行了有限元离散化的受力分析。通过对空调系统和滚动转子压缩机的改造，对空调系统在不同工况下的多点温度、压力和制冷量进行了实验测量。同时，利用噪声采集设备对叶片背面和垂直方向的系统噪声进行测量，并对噪声谱进行分析。结果表明：与额定冷却工况相比，低速工况下叶片的最大倾角减小了14.2%，倾角变化范围减小了52.4%，叶片的二次运动减弱。对叶片在低速时的分离进行了计算，并与噪声谱实验结果进行了对比，验证了本文数学模型的合理性。叶片分离计算和实验结果表明，叶片与滚动转子分离后，压气机容积效率降至80%以下，并产生冲击噪声，对叶片后部的噪声变化有显著影响。低速时叶片侧纵向气力减小和润滑条件差是导致叶片在180°转角前分离的主要原因。

{"title":"Research on the motion characteristics of sliding vane in rolling piston compressor under low-speed condition","authors":"Yanjun Du , Shunan Li , Jianhua Wu , Qingwen Liu , Zibo Zhao","doi":"10.1016/j.ijrefrig.2025.12.021","DOIUrl":"10.1016/j.ijrefrig.2025.12.021","url":null,"abstract":"<div><div>The rolling rotor compressors frequently face operational challenges such as vane impact noise and impaired efficiency under low-speed conditions, which hinder the ability to meet the growing demand for energy-efficient and comfortable air conditioning systems. It is essential to investigate the lubrication and motion characteristics of the vane side in rolling rotor compressors for room air conditioners under low-speed conditions, in order to ensure compressor performance and system comfort during low-speed operation. This paper conducted the force analysis based on the finite element discretization of the oil film area on the vane side. Experiments were conducted to measure the temperature, pressure, and cooling capacity at multiple points in the air conditioning system under different operating conditions by modifying the air conditioning system and rolling rotor compressor. Meanwhile, noise collection equipment was used to measure the system noise at the back of the vane and in its vertical direction, and the noise spectrum was analyzed. The results show that the maximum inclination angle of the vane decreases by 14.2 % at low-speed conditions, the range of inclination angle variation shrinks by 52.4 %, and the secondary motion of the vane weakens, compared to the rated cooling condition. Furthermore, the detachment of the vane at low-speed was calculated and compared with the experimental results of noise spectrum, verifying the rationality of the mathematical model in this paper. The calculation and experimental results of vane detachment show that after the vane detaches from the rolling rotor, the compressor volumetric efficiency drops below 80 %, and impact noise is generated, which has a significant impact on the noise variation at the back of the vane. The decrease in longitudinal gas force and poor lubrication condition on the vane side at low-speed are the main reasons for the vane detaching before the 180° rotation angle.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 522-532"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145836448","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

Quantifying emissions from cold chain transport of apples to and within Norway 量化苹果冷链运输到挪威和在挪威境内的排放量

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-12-16 DOI: 10.1016/j.ijrefrig.2025.12.016

Patrick Hadamitzky, Sophie Kendler, Kristina Norne Widell, Erlend Indergård

Norway imports a significant share of its fruits and vegetables, contributing to transportation-related greenhouse gas emissions. This study maps the cold chain transportation networks of imported and domestic apples in Norway, assessing CO₂e emissions from the point of export to individual supermarkets. It represents the most detailed analysis of its kind, tracing the journey from specific export locations through main and regional warehouses to retail outlets across the country. The Norwegian food market is dominated by three major retail chains, each operating its own distribution system, often supported by a central third-party importer. Most transport relies on trucks, which raises sustainability concerns due to fossil fuel use and potential refrigerant leakage. The coexistence of main and regional warehouses increases transport frequency and energy consumption, particularly for perishable goods like apples. Improving transparency across supply chains is essential to optimise energy use, reduce food loss, and lower emissions. By improving cooling technologies, reform transport logistics, and integrating innovative sustainability practices, Norway’s food sector can address growing cooling demands while advancing toward reduced carbon footprints. On average, refrigerated transport of apples in Norway emits 0.166 kg CO₂e per kilogram. Of this, 0.161 kg CO₂e/kg stems from transport, 0.003 kg CO₂e/kg from refrigerant leakage, and 0.001 kg CO₂e/kg from the refrigeration process. Under current assumptions and with the use of modern refrigerants, leakage accounts for approximately 2 % of total emissions. These findings highlight the importance of targeted interventions in transport and refrigeration to support more sustainable food systems.

挪威的水果和蔬菜有很大一部分是进口的，这导致了与交通有关的温室气体排放。该研究绘制了挪威进口和国内苹果的冷链运输网络，评估了从出口到单个超市的二氧化碳排放量。它代表了同类分析中最详细的分析，追踪了从特定出口地点通过主要和区域仓库到全国各地零售店的旅程。挪威食品市场由三大零售连锁店主导，每家连锁店都有自己的分销系统，通常由中央第三方进口商提供支持。大多数运输依赖于卡车，由于化石燃料的使用和潜在的制冷剂泄漏，这引起了可持续性问题。主仓库和区域仓库的共存增加了运输频率和能源消耗，特别是像苹果这样的易腐货物。提高整个供应链的透明度对于优化能源使用、减少粮食损失和降低排放至关重要。通过改进冷却技术、改革运输物流和整合创新的可持续性实践，挪威食品部门可以在减少碳足迹的同时解决日益增长的冷却需求。在挪威，苹果的冷藏运输平均每公斤排放0.166公斤二氧化碳。其中，0.161 kg CO₂e/kg来自运输，0.003 kg CO₂e/kg来自制冷剂泄漏，0.001 kg CO₂e/kg来自制冷过程。在目前的假设和使用现代制冷剂的情况下，泄漏约占总排放量的2%。这些发现强调了在运输和冷藏方面采取有针对性的干预措施以支持更可持续的粮食系统的重要性。

{"title":"Quantifying emissions from cold chain transport of apples to and within Norway","authors":"Patrick Hadamitzky, Sophie Kendler, Kristina Norne Widell, Erlend Indergård","doi":"10.1016/j.ijrefrig.2025.12.016","DOIUrl":"10.1016/j.ijrefrig.2025.12.016","url":null,"abstract":"<div><div>Norway imports a significant share of its fruits and vegetables, contributing to transportation-related greenhouse gas emissions. This study maps the cold chain transportation networks of imported and domestic apples in Norway, assessing CO₂e emissions from the point of export to individual supermarkets. It represents the most detailed analysis of its kind, tracing the journey from specific export locations through main and regional warehouses to retail outlets across the country. The Norwegian food market is dominated by three major retail chains, each operating its own distribution system, often supported by a central third-party importer. Most transport relies on trucks, which raises sustainability concerns due to fossil fuel use and potential refrigerant leakage. The coexistence of main and regional warehouses increases transport frequency and energy consumption, particularly for perishable goods like apples. Improving transparency across supply chains is essential to optimise energy use, reduce food loss, and lower emissions. By improving cooling technologies, reform transport logistics, and integrating innovative sustainability practices, Norway’s food sector can address growing cooling demands while advancing toward reduced carbon footprints. On average, refrigerated transport of apples in Norway emits 0.166 kg CO₂e per kilogram. Of this, 0.161 kg CO₂e/kg stems from transport, 0.003 kg CO₂e/kg from refrigerant leakage, and 0.001 kg CO₂e/kg from the refrigeration process. Under current assumptions and with the use of modern refrigerants, leakage accounts for approximately 2 % of total emissions. These findings highlight the importance of targeted interventions in transport and refrigeration to support more sustainable food systems.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 482-492"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145836455","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 of operating characteristics of a novel rack-level hybrid cooling system for data centers 数据中心新型机架级混合冷却系统运行特性实验研究

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-12-08 DOI: 10.1016/j.ijrefrig.2025.12.010

Tongzhi Yang , Xi’an Liu , Yifan Zhao , Weixing Yuan , Hao Cheng , Kexian Ren

Conventional data center air-conditioners consume excessive energy. Rack-level hybrid cooling systems combining a pump-driven heat pipe (PHP) and a vapor-compression (VC) cycle provide a promising alternative but often encounter refrigerant starvation in evaporators. Therefore, we previously proposed a novel rack-level hybrid cooling system adopting gas–liquid separation in all modes and a subcooler. However, prior work studied its energy efficiency ratio (EER_cp) only at fixed vapor quality, leaving key operating characteristics unexplored. To address these gaps, this paper experimentally investigated the novel system’s response characteristics under varying vapor quality, condenser-side disturbances, and non-uniform cooling loads, including variations in mode-switching temperatures, EER_cp, and refrigerant state. Experiments were conducted on a prototype setup with five plate heat exchangers representing rack-level evaporators, at evaporating temperatures of 23.5–24.0 °C to match the ASHRAE-recommended 27 °C server room. Results show that reducing the evaporator outlet vapor quality from 0.76 to 0.58 decreased EER_cp by 13–30 %, shifted mode-switching temperatures by 2–4 °C, and increased evaporator inlet subcooling by 1.6–2.9 °C. The 6 °C disturbances in the condenser inlet water temperature (T_con,win) caused transient fluctuations in evaporator inlet subcooling, yet it still remained above 0 °C to maintain the flow distribution among evaporators. Under severe non-uniform cooling loads, the system effectively prevented local hotspots, with EER_cp decreasing by only 0.1–0.2 in vapor-compressor-driven and hybrid-driven modes, and remaining 127 in liquid-pump-driven mode. Although based on prototype experiments, these findings provided useful insights into strategies for operating the novel system in practical applications.

传统数据中心空调能耗大。结合泵驱动热管（PHP）和蒸汽压缩（VC）循环的机架级混合冷却系统提供了一个有前途的替代方案，但经常遇到蒸发器中的制冷剂短缺。因此，我们之前提出了一种新型的机架级混合冷却系统，采用所有模式的气液分离和一个过冷却器。然而，之前的工作只研究了固定蒸汽质量下的能效比（EERcp），而没有探索关键的工作特性。为了解决这些问题，本文通过实验研究了该系统在不同蒸汽质量、冷凝器侧扰动和非均匀冷却负荷下的响应特性，包括模式切换温度、EERcp和制冷剂状态的变化。实验在一个原型装置上进行，其中有5个板式换热器代表机架级蒸发器，蒸发温度为23.5-24.0°C，以匹配ashrae推荐的27°C服务器机房。结果表明，当蒸发器出口蒸汽质量从0.76降低到0.58时，EERcp降低13 ~ 30%，模式切换温度升高2 ~ 4℃，蒸发器进口过冷度升高1.6 ~ 2.9℃。冷凝器进水温度（Tcon,win）的6℃扰动引起蒸发器进口过冷度的瞬态波动，但仍保持在0℃以上，以维持蒸发器之间的流量分配。在严重的非均匀冷却负荷下，系统有效地防止了局部热点，在蒸汽压缩机驱动和混合驱动模式下，EERcp仅降低了0.1-0.2，在液泵驱动模式下，EERcp仍降低了127。尽管基于原型实验，这些发现为在实际应用中操作新系统的策略提供了有用的见解。

{"title":"Experimental study of operating characteristics of a novel rack-level hybrid cooling system for data centers","authors":"Tongzhi Yang , Xi’an Liu , Yifan Zhao , Weixing Yuan , Hao Cheng , Kexian Ren","doi":"10.1016/j.ijrefrig.2025.12.010","DOIUrl":"10.1016/j.ijrefrig.2025.12.010","url":null,"abstract":"<div><div>Conventional data center air-conditioners consume excessive energy. Rack-level hybrid cooling systems combining a pump-driven heat pipe (PHP) and a vapor-compression (VC) cycle provide a promising alternative but often encounter refrigerant starvation in evaporators. Therefore, we previously proposed a novel rack-level hybrid cooling system adopting gas–liquid separation in all modes and a subcooler. However, prior work studied its energy efficiency ratio (<em>EER</em><sub>cp</sub>) only at fixed vapor quality, leaving key operating characteristics unexplored. To address these gaps, this paper experimentally investigated the novel system’s response characteristics under varying vapor quality, condenser-side disturbances, and non-uniform cooling loads, including variations in mode-switching temperatures, <em>EER</em><sub>cp</sub>, and refrigerant state. Experiments were conducted on a prototype setup with five plate heat exchangers representing rack-level evaporators, at evaporating temperatures of 23.5–24.0 °C to match the ASHRAE-recommended 27 °C server room. Results show that reducing the evaporator outlet vapor quality from 0.76 to 0.58 decreased <em>EER</em><sub>cp</sub> by 13–30 %, shifted mode-switching temperatures by 2–4 °C, and increased evaporator inlet subcooling by 1.6–2.9 °C. The 6 °C disturbances in the condenser inlet water temperature (<em>T</em><sub>con,win</sub>) caused transient fluctuations in evaporator inlet subcooling, yet it still remained above 0 °C to maintain the flow distribution among evaporators. Under severe non-uniform cooling loads, the system effectively prevented local hotspots, with <em>EER</em><sub>cp</sub> decreasing by only 0.1–0.2 in vapor-compressor-driven and hybrid-driven modes, and remaining 127 in liquid-pump-driven mode. Although based on prototype experiments, these findings provided useful insights into strategies for operating the novel system in practical applications.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 323-333"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733326","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

Quantitative evaluation of the evaporator configuration’s implications on the performance enhancement in CO2 thermal management system for electric vehicle 蒸发器配置对电动汽车CO2热管理系统性能提升影响的定量评价

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-12-02 DOI: 10.1016/j.ijrefrig.2025.11.029

Jianmin Fang , Yichen Zhang , Fan Jia , Xiang Yin , Bin Chen , Feng Cao , Xiaolin Wang

Enhancing the cooling performance of CO₂ thermal management systems in electric vehicles remains a critical research focus. Although multi-path evaporators improve thermal efficiency by increasing the evaporative temperature, their associated pressure drop reduces compressor suction pressure, presenting a key trade-off in system performance. To investigate this coupled problem, a mathematical model of CO2 thermal systems with varying evaporator configurations was developed, and an experimental test bench was established to analyze their impact on comprehensive performance. The effect of the evaporator pass on the cooling performance under different operating conditions was firstly studied, which both involved the influence of the heat transfer enhancement and pressure drop. Moreover, the evaporative pressure, suction pressure and the mean temperature were analyzed to reveal the dominating parameters under different conditions. An optimized heat exchanger configuration was concluded (which gained a 34.5 % COP increment with a 9.4 % bigger cooling capacity at 35 °C ambient), and it was further validated by the experimental investigations. Finally, experimental comparison was conducted for thermal management systems with different exchanger configurations. The results showed that the evaporator had an optimal pass under larger cooling capacities requirement, but the performance was always increased with the evaporator pass under a smaller cooling capacity. The pressure drop had a dominating effect for the larger cooling capacities operation conditions, and the evaporator required different design for a better performance according to the maximum cooling demand. It could provide a reference of the better system design for different types of electric vehicles.

提高电动汽车二氧化碳热管理系统的冷却性能仍然是一个关键的研究热点。尽管多路径蒸发器通过提高蒸发温度来提高热效率，但其相关的压降降低了压缩机吸入压力，这是系统性能的关键权衡。为了研究这一耦合问题，建立了不同蒸发器配置的CO2热系统数学模型，并建立了实验试验台，分析了不同蒸发器配置对系统综合性能的影响。首先研究了不同工况下蒸发器通道对冷却性能的影响，包括传热强化和压降的影响。并对蒸发压力、吸入压力和平均温度进行了分析，揭示了不同工况下的主要参数。优化后的换热器配置（在35°C环境下，COP增加34.5%，制冷量增加9.4%），并通过实验进一步验证。最后，对不同换热器配置的热管理系统进行了实验比较。结果表明，当制冷量要求较大时，蒸发器具有最优通程，但在制冷量要求较小时，蒸发器性能随通程的增大而增大。在较大制冷量工况下，压降起主导作用，根据最大制冷量需求，对蒸发器进行不同的设计以获得更好的性能。可以为不同类型的电动汽车提供更好的系统设计参考。

{"title":"Quantitative evaluation of the evaporator configuration’s implications on the performance enhancement in CO2 thermal management system for electric vehicle","authors":"Jianmin Fang , Yichen Zhang , Fan Jia , Xiang Yin , Bin Chen , Feng Cao , Xiaolin Wang","doi":"10.1016/j.ijrefrig.2025.11.029","DOIUrl":"10.1016/j.ijrefrig.2025.11.029","url":null,"abstract":"<div><div>Enhancing the cooling performance of CO<sub>2</sub> thermal management systems in electric vehicles remains a critical research focus. Although multi-path evaporators improve thermal efficiency by increasing the evaporative temperature, their associated pressure drop reduces compressor suction pressure, presenting a key trade-off in system performance. To investigate this coupled problem, a mathematical model of CO2 thermal systems with varying evaporator configurations was developed, and an experimental test bench was established to analyze their impact on comprehensive performance. The effect of the evaporator pass on the cooling performance under different operating conditions was firstly studied, which both involved the influence of the heat transfer enhancement and pressure drop. Moreover, the evaporative pressure, suction pressure and the mean temperature were analyzed to reveal the dominating parameters under different conditions. An optimized heat exchanger configuration was concluded (which gained a 34.5 % COP increment with a 9.4 % bigger cooling capacity at 35 °C ambient), and it was further validated by the experimental investigations. Finally, experimental comparison was conducted for thermal management systems with different exchanger configurations. The results showed that the evaporator had an optimal pass under larger cooling capacities requirement, but the performance was always increased with the evaporator pass under a smaller cooling capacity. The pressure drop had a dominating effect for the larger cooling capacities operation conditions, and the evaporator required different design for a better performance according to the maximum cooling demand. It could provide a reference of the better system design for different types of electric vehicles.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 287-298"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733330","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

Simultaneous heat and mass transfer in transient dovetail metallic porous fin made of aluminium and copper metals: Analysing efficiency and thermal dynamics under dehumidification 铝和铜金属制成的瞬态燕尾金属多孔翅片的同时传热传质：除湿效率和热动力学分析

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-02-01 Epub Date: 2025-12-11 DOI: 10.1016/j.ijrefrig.2025.12.011

P.L.Pavan Kumar , B.J. Gireesha , P. Venkatesh

The presents study investigates transient thermal analysis of porous dovetail fin made of copper (

C u

) and aluminium (

A l

) under dehumidification condition, where simultaneous heat and mass transfer occurs through surface condensation when the fin temperature drops below the ambient dew point. The flow and transport through the porous structure are modelled using Darcy’s law and the nonlinear governing equations are solved numerically using Finite Difference Method (FDM) with results showing good agreement with existing literature confirming the model’s accuracy and reliability. Results reveal that

C u

fin demonstrate superior heat dissipation and efficiency exhibiting a 119.09 % rise in temperature distribution compared with 178.10 % for

A l

attributed to

C u

higher thermal conductivity and enhanced heat diffusion capability. The dovetail configuration yields better thermal performance than the rectangular fin with temperature rises of 178.10 % (

A l

) and 119.09 % (

C u

) owing to its tapered profile that reduces axial thermal resistance and promotes effective condensation. Parametric evaluation reveals that increasing Relative Humidity (

R H

) by 400 % decreases temperature distribution by 131.58 % in

A l

and 81.65 % in

C u

due to intensified latent heat absorption, while a 200 % variation in taper ratio (

C

) alters it by 14.50 % and 10.06 %, respectively. These results confirm that

C u

dovetail fin achieve higher efficiency and more stable condensation dynamics, offering practical applicability for compact heat exchangers, air-cooling units and dehumidification-based thermal management systems.

本文研究了在除湿条件下，由铜（Cu）和铝（Al）制成的多孔燕尾翅的瞬态热分析，当翅片温度降至环境露点以下时，通过表面冷凝同时进行传热传质。采用达西定律对多孔结构中的流动和输运进行了建模，并采用有限差分法对非线性控制方程进行了数值求解，结果与已有文献吻合较好，证实了模型的准确性和可靠性。结果表明，Cu翅片具有优异的散热性能和散热效率，其温度分布比Al翅片的温度分布高119.09%，而Al翅片的温度分布比Al翅片的温度分布高178.10%。与矩形翅片相比，燕尾翼的温度上升幅度分别为178.10% （Al）和119.09% (Cu)，因为燕尾翼的锥形外形减小了轴向热阻，促进了有效冷凝。参数评价表明，相对湿度（RH）每增加400%，由于潜热吸收的增强，Al和Cu的温度分布分别减少131.58%和81.65%，而锥度比(C)变化200%，分别使Al和Cu的温度分布减少14.50%和10.06%。这些结果证实，Cu燕尾翼可以实现更高的效率和更稳定的冷凝动力学，为紧凑型热交换器、风冷装置和基于除湿的热管理系统提供实用的适用性。

{"title":"Simultaneous heat and mass transfer in transient dovetail metallic porous fin made of aluminium and copper metals: Analysing efficiency and thermal dynamics under dehumidification","authors":"P.L.Pavan Kumar , B.J. Gireesha , P. Venkatesh","doi":"10.1016/j.ijrefrig.2025.12.011","DOIUrl":"10.1016/j.ijrefrig.2025.12.011","url":null,"abstract":"<div><div>The presents study investigates transient thermal analysis of porous dovetail fin made of copper (<span><math><mrow><mi>C</mi><mi>u</mi></mrow></math></span>) and aluminium (<span><math><mrow><mi>A</mi><mi>l</mi></mrow></math></span>) under dehumidification condition, where simultaneous heat and mass transfer occurs through surface condensation when the fin temperature drops below the ambient dew point. The flow and transport through the porous structure are modelled using Darcy’s law and the nonlinear governing equations are solved numerically using Finite Difference Method (FDM) with results showing good agreement with existing literature confirming the model’s accuracy and reliability. Results reveal that <span><math><mrow><mi>C</mi><mi>u</mi></mrow></math></span> fin demonstrate superior heat dissipation and efficiency exhibiting a 119.09 % rise in temperature distribution compared with 178.10 % for <span><math><mrow><mi>A</mi><mi>l</mi></mrow></math></span> attributed to <span><math><mrow><mi>C</mi><mi>u</mi></mrow></math></span> higher thermal conductivity and enhanced heat diffusion capability. The dovetail configuration yields better thermal performance than the rectangular fin with temperature rises of 178.10 % (<span><math><mrow><mi>A</mi><mi>l</mi></mrow></math></span>) and 119.09 % (<span><math><mrow><mi>C</mi><mi>u</mi></mrow></math></span>) owing to its tapered profile that reduces axial thermal resistance and promotes effective condensation. Parametric evaluation reveals that increasing Relative Humidity (<span><math><mrow><mi>R</mi><mi>H</mi></mrow></math></span>) by 400 % decreases temperature distribution by 131.58 % in <span><math><mrow><mi>A</mi><mi>l</mi></mrow></math></span> and 81.65 % in <span><math><mrow><mi>C</mi><mi>u</mi></mrow></math></span> due to intensified latent heat absorption, while a 200 % variation in taper ratio (<span><math><mi>C</mi></math></span>) alters it by 14.50 % and 10.06 %, respectively. These results confirm that <span><math><mrow><mi>C</mi><mi>u</mi></mrow></math></span> dovetail fin achieve higher efficiency and more stable condensation dynamics, offering practical applicability for compact heat exchangers, air-cooling units and dehumidification-based thermal management systems.</div></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":"182 ","pages":"Pages 430-446"},"PeriodicalIF":3.8,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145786650","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