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

Application of eXtreme gradient boosting in the performance prediction of a refrigeration system working with alternative refrigerants 极值梯度增压在替代制冷剂制冷系统性能预测中的应用

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-20 DOI: 10.1016/j.ijrefrig.2025.12.020

Yair A. Andrade-Ambriz , J. Serrano-Arellano , J.J. García-Pabón , V. Peréz-García , J.M. Belman-Flores

Refrigeration is essential to many sectors of society, including food preservation, the pharmaceutical industry, industrial processes, and thermal comfort. Current refrigeration systems, based on vapor compression, must become more energy-efficient and reduce their environmental impact. However, testing different low global warming potential refrigerants requires time and test benches. Several mathematical or heuristic models can simulate the behavior of a refrigeration system. These models allow computationally testing different types of experimental benches or configurations. This study utilizes eXtreme Gradient Boosting, a machine learning algorithm, to simulate the performance of a refrigeration system using a minimal amount of experimental data. This model uses temperatures and secondary flows in the condenser and evaporator as inputs. With this information, the model can predict the behavior of the coefficient of performance, power consumption, cooling capacity, refrigerant flow rate, and up to four refrigerants, such as R134a, R513A, R516A, and R1234ze(E). Additionally, the model achieves an overall coefficient of determination greater than 0.98 and an overall accuracy of 96.13 %. These enable the simulation of different operating values of the experimental bench to determine the most effective refrigerant for achieving the highest coefficient of performance; thus, R1234ze(E) and R513A are those that represent the highest COP.

制冷对社会的许多部门都是必不可少的，包括食品保存、制药工业、工业过程和热舒适。目前基于蒸汽压缩的制冷系统必须变得更加节能，并减少对环境的影响。然而，测试不同的低全球变暖潜能值制冷剂需要时间和试验台。几个数学或启发式模型可以模拟制冷系统的行为。这些模型允许对不同类型的试验台或配置进行计算测试。本研究利用eXtreme Gradient Boosting，一种机器学习算法，使用最少的实验数据来模拟制冷系统的性能。该模型使用冷凝器和蒸发器中的温度和二次流作为输入。利用这些信息，该模型可以预测性能系数、功耗、制冷量、制冷剂流量以及多达四种制冷剂（如R134a、R513A、R516A和R1234ze(E)）的行为。此外，该模型的总体决定系数大于0.98，总体精度为96.13%。这使得模拟不同的操作值的实验平台，以确定最有效的制冷剂，以实现最高的性能系数；因此，R1234ze(E)和R513A代表最高COP。

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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 : 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。

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引用次数: 0

Development of a magnetic single-sinker densimeter based on direct displacement regulation over a wide temperature range from 85 to 350 K and pressures up to 15 MPa 基于直接位移调节的磁单沉密度计的开发，温度范围从85到350 K，压力可达15 MPa

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-19 DOI: 10.1016/j.ijrefrig.2025.12.019

Jiadong Sun, Yilun Yang, Yonghua Huang

A magnetic-suspension single-sinker densimeter was developed for refrigerants over a broad temperature range (85–350 K) and at pressures up to 15 MPa. The densimeter incorporates adjustable temperature-synchronized cold shields and an innovative direct displacement regulation method that sets predefined displacement parameters to dynamically regulate the electronic magnet current. This approach ensures sinker stability through controlled current adjustments, significantly enhancing operational efficiency and adaptability across diverse fluids and temperature conditions. A segmented range approach was employed for temperature regulation with uncertainties of ±0.1 K (85–150 K), ±0.05 K (150–290 K), and ±0.01 K (290–350 K). When validated against NIST REFPROP 10.0 using R290, nitrogen, and argon as specimens, the system achieved a maximum absolute relative deviation in liquid density of within 0.6 % across all temperatures.

研制了一种磁悬浮式单沉式密度计，可在宽温度范围（85-350 K）和高达15 MPa的压力下测量制冷剂。密度计采用可调温度同步冷护罩和创新的直接位移调节方法，设置预定义的位移参数来动态调节电子磁铁电流。这种方法通过可控的电流调节确保了下沉器的稳定性，显著提高了作业效率和对不同流体和温度条件的适应性。温度调节采用分段范围法，不确定度分别为±0.1 K （85 ~ 150 K）、±0.05 K （150 ~ 290 K）和±0.01 K （290 ~ 350 K）。当使用R290、氮气和氩气作为样品对NIST REFPROP 10.0进行验证时，系统在所有温度下的液体密度最大绝对相对偏差在0.6%以内。

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 : 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。

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引用次数: 0

Improving energy efficiency in pear storage through dynamic controlled atmosphere (DCA) 动态控制气氛（DCA）提高梨贮藏能效

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-16 DOI: 10.1016/j.ijrefrig.2025.12.015

Hoang Minh Phan , Bert E. Verlinden , Maarten L.A.T.M. Hertog , Pieter Verboven , Bart M. Nicolai

The energy efficiency of ‘Conference’ pear storage was assessed for different storage strategies, including dynamic controlled atmosphere (DCA) at different temperatures and controlled atmosphere (CA) at varying temperatures and O₂ levels. Storage at -1 °C in 3 kPa O₂ and 0.7 kPa CO₂ was used as a benchmark. Direct respiration measurements during the storage period showed that DCA reduced respiratory heat by 30–40 % compared with the benchmark, even at slightly elevated temperatures. A simulation-based energy assessment revealed that DCA could reduce the total heat load in a storage room by 8–16 %. Fan operation was found to account for the largest share of the total heat load (up to 50 %), while the respiratory heat contributed around 10–30 %. Among all experimental strategies, DCA at -1 °C reduced the total heat load by ∼8 %, and maintained good firmness and skin colour without inducing internal browning after long-term storage. This makes it the most optimal approach to balance fruit quality and energy savings.

对不同贮藏策略（包括不同温度下的动态控制气氛（DCA）和不同温度和O2水平下的控制气氛（CA））下“会议”梨贮藏的能源效率进行了评价。以-1℃，3kpa O2和0.7 kPa CO2作为基准。储存期间的直接呼吸测量表明，与基准相比，即使在稍微升高的温度下，DCA也能降低30 - 40%的呼吸热。一项基于模拟的能源评估显示，DCA可以将储藏室的总热负荷降低8 - 16%。研究发现，风扇运行占总热负荷的最大份额（高达50%），而呼吸热贡献约10 - 30%。在所有实验策略中，-1°C的DCA使总热负荷降低了~ 8%，并在长期储存后保持了良好的紧致度和皮肤颜色，而不会引起内部褐变。这使得它成为平衡水果质量和节约能源的最佳方法。

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引用次数: 0

Improvements and intelligence integration of virtual refrigerant charge (VRC) sensor 虚拟制冷剂充注量传感器的改进与智能集成

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-16 DOI: 10.1016/j.ijrefrig.2025.12.017

Yue Zheng , Hua Han , Jun Xiong , Hua Zhang , Xun Cao , Bo Gu , Wenjie Dai , Xu Gao , Weiqi Yi

Refrigerant leakage significantly undermines the energy efficiency and operational safety of variable refrigerant flow (VRF) systems, making accurate prediction of refrigerant charge critically important. Conventional diagnostic approaches are often costly, reliant on complex models, non-quantitative, and lack generalization, which restricts their practical deployment. To address these limitations, a series of enhancements and intelligent integration were introduced to the virtual refrigerant charge (VRC) sensor. An operating-condition matching strategy was first employed to establish an exVRC sensor for condition extending. An exponentially weighted moving average (EWMA) control chart was then incorporated to construct an exVRC-E sensor for oscillation mitigation. Finally, a deep learning-based Residual Neural Network (ResNet) was established and coupled with the exVRC-E sensor to produce an AI-knowledge dual-driven intelligent sensor, exVRC-ER. Experimental validation on a 33.5 kW VRF system under one rated and fourteen off-rated conditions showed that compared with the original VRC sensor, the exVRC sensor reduces MAPE by 16.21 % under extreme off-rated conditions, corresponding to a 74 % relative reduction. The exVRC-E sensor further lowers oscillation amplitude by 84 % and reduces false-alarm risk during normal operation. Across all conditions, the final exVRC-ER intelligent sensor integrated with deep learning achieves the best performance, with a 71.8 % relative reduction in MAPE and a 1.21 kg decrease in root mean square error (RMSE) compared with the original VRC sensor. These results indicate a significant potential for precise quantification of refrigerant leakage, highlighting their importance for enhancing the efficient operation and intelligent maintenance of HVAC systems.

制冷剂泄漏严重影响了VRF （variable制冷剂flow）系统的能效和运行安全性，因此准确预测制冷剂充注量至关重要。传统的诊断方法往往是昂贵的，依赖于复杂的模型，非定量的，缺乏泛化，这限制了他们的实际部署。为了解决这些限制，虚拟制冷剂充注（VRC）传感器引入了一系列增强功能和智能集成。首先采用工况匹配策略，建立了工况扩展exVRC传感器。然后结合指数加权移动平均（EWMA）控制图构建exVRC-E传感器以缓解振荡。最后，建立了基于深度学习的残差神经网络（ResNet），并与exVRC-E传感器相结合，形成ai -知识双驱动智能传感器exVRC-ER。在一个33.5 kW VRF系统上进行了1个额定工况和14个非额定工况的实验验证，结果表明，与原始VRC传感器相比，exVRC传感器在极端非额定工况下的MAPE降低了16.21%，相对降低了74%。exVRC-E传感器进一步降低了84%的振荡幅度，并降低了正常运行时的误报风险。在所有条件下，最终集成深度学习的exVRC-ER智能传感器的性能最佳，与原始VRC传感器相比，MAPE相对降低了71.8%，均方根误差（RMSE）降低了1.21 kg。这些结果表明了制冷剂泄漏精确量化的巨大潜力，突出了它们对提高HVAC系统的高效运行和智能维护的重要性。

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引用次数: 0

Impact of superchilling storage temperatures on beef quality: Micro-CT analysis of ice recrystallization kinetics in partially frozen samples 超低温储存温度对牛肉品质的影响：部分冷冻样品冰再结晶动力学的显微ct分析

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-12 DOI: 10.1016/j.ijrefrig.2025.12.013

Anjelina W Mwakosya, Graciela Alvarez, Fatou Toutie Ndoye

This study aims to investigate the microstructure changes of partially frozen beef under different superchilling storage conditions and relate these changes to quality degradation. Beef samples were partially frozen in an air blast freezer with a heat transfer coefficient of 112 W/m²K and an air temperature of ‒32 °C for 2 min following storage at ‒1.8 °C, ‒2.8 °C, ‒4 °C and ‒5 °C for 21 days. "X-ray micro-computed tomography (µCT), a non-destructive 3D imaging technique was used to visualize and quantify ice crystal characteristic, including ice volume fractions, ice crystal size, number and distribution". Recrystallization kinetics were modelled using the asymptotic Ostwald ripening equation and correlated with quality degradation rate through Pearson correlation analysis. Immediately after partial freezing, the average initial ice volume fraction, mean equivalent diameter, and crystal number were 31 ± 1 %, 36.0 ± 0.3 µm, and 421,182 ± 16,524, respectively. Over storage time, ice volume fraction and crystal size increased significantly (p < 0.05), while crystal number decreased, leading to increased drip loss, and reduced firmness of beef upon thawing. In addition, recrystallization rates increased significantly (p < 0.05) with decreasing storage temperature specifically within a range of ‒1.8 °C to ‒5 °C as lower temperatures resulted in higher ice fractions and more heterogeneous crystal size distributions, thereby promoting recrystallization. A high regression coefficient (R² > 0.9) indicated a strong fit of the recrystallization rate’s temperature dependence to the Arrhenius model. Recrystallization rate was strongly correlated with all quality degradation rates (R² > 0.9). Overall, this study demonstrates the critical role of recrystallization in driving deterioration of partially frozen beef and highlights the value of X‒ray µCT for non-invasive monitoring microstructure changes during superchilled storage.

本研究旨在研究不同超低温储存条件下部分冷冻牛肉的微观结构变化，并将这些变化与品质退化联系起来。牛肉样品在-1.8°C、-2.8°C、-4°C和-5°C的条件下，在传热系数为112 W/m2K、空气温度为-32°C的鼓风冷冻室中部分冷冻2分钟，保存21天。“x射线微计算机断层扫描（µCT）是一种非破坏性的3D成像技术，用于可视化和量化冰晶特征，包括冰体积分数、冰晶大小、数量和分布”。再结晶动力学采用渐近奥斯特瓦尔德成熟方程进行建模，并通过Pearson相关分析与质量退化率进行关联。部分冻结后即刻的平均初始冰体积分数为31±1%，平均等效直径为36.0±0.3µm，晶数为421,182±16,524。随着贮藏时间的延长，冰体积分数和晶体尺寸显著增加（p < 0.05），晶体数量减少，导致滴漏损失增加，解冻后牛肉的硬度降低。此外，随着温度的降低，再结晶率显著增加（p < 0.05），特别是在-1.8°C至-5°C范围内，温度越低，冰馏分越高，晶粒尺寸分布越不均匀，从而促进了再结晶。较高的回归系数（R2 > 0.9）表明再结晶速率的温度依赖性与Arrhenius模型非常吻合。再结晶率与所有质量降解率呈显著正相关（R2 > 0.9）。总体而言，本研究证明了再结晶在驱动部分冷冻牛肉变质中的关键作用，并强调了x射线微CT在超冷储存过程中无创监测微观结构变化的价值。

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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 : 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。

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引用次数: 0

Thermo-economic performance of an integrated unglazed solar-air dual-source heat pump: an experimental investigation 集成无玻璃太阳能-空气双源热泵的热经济性能实验研究

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-10 DOI: 10.1016/j.ijrefrig.2025.12.012

Sujie Liu , Jiaxuan Pu , Jiaxing Li , Huan Zhang , Tianzhen Ye , Xinyu Zhang , Zhihao Wan , Zhaoying Wang , Xianwang Fan , Wandong Zheng

The ongoing integration of renewable energy into power grids is driving a transition towards distributed and multi-source energy frameworks in building energy systems. Solar-assisted heat pumps, as the emerging distributed multi-source heating systems, face persistent challenges including operating instability, seasonal limitations, and complex control requirements. To address these shortcomings, this study develops a novel integrated unglazed solar-air dual-source heat pump (USAHP) system. The system synergistically harnesses dual renewable energy sources by incorporating high-efficiency finned tubes with absorbing coating and reflectors into a compound solar air collector-evaporator. The integration could maximize evaporator output within a constrained area. Experimental investigations are conducted to evaluate and analyze the system performance, specifically examining the effects of operating parameters and collector-evaporator configuration on thermal collection efficiency. Results demonstrate that among three key parameters, solar irradiance and ambient air temperature exert significantly positive influences on system performance, while relative humidity exhibits weak correlation. The reflector-equipped collector-evaporator enhances solar irradiance absorption by 27–54 %. The proposed USAHP achieves superior frost suppression and enhanced energy efficiency by elevating the evaporation temperature. The evaporation temperature of USAHP increases by up to 3.2 °C under experimental conditions, and COP improves by up to 19.3 % compared to conventional air-source and solar-air assisted heat pump systems. Furthermore, a payback period of 3.18 years demonstrates the economic viability of USAHP. This research represents key advancement in frost mitigation mechanisms and demonstrates substantial improvements in energy efficiency, thereby advancing heat pump technology for multi-source energy applications.

可再生能源与电网的持续整合正在推动建筑能源系统向分布式和多源能源框架的过渡。太阳能热泵作为新兴的分布式多源供热系统，面临着运行不稳定性、季节性限制和复杂控制要求等长期存在的挑战。为了解决这些缺点，本研究开发了一种新型集成无釉太阳能-空气双源热泵（USAHP）系统。该系统通过将高效翅片管与吸收涂层和反射器结合到复合太阳能空气收集器-蒸发器中，协同利用双重可再生能源。集成可以在有限的区域内最大化蒸发器输出。实验研究对系统性能进行了评估和分析，具体考察了运行参数和集热器-蒸发器配置对集热效率的影响。结果表明，在三个关键参数中，太阳辐照度和环境温度对系统性能有显著的正向影响，相对湿度对系统性能有弱相关。配备反射器的集热器-蒸发器提高了27 - 54%的太阳辐照度吸收量。所提出的USAHP通过提高蒸发温度实现了优越的抑霜和提高的能源效率。在实验条件下，USAHP的蒸发温度提高了3.2°C，与传统的空气源和太阳能-空气辅助热泵系统相比，COP提高了19.3%。此外，3.18年的投资回收期证明了USAHP的经济可行性。这项研究代表了霜冻缓解机制的关键进展，并证明了能源效率的实质性改进，从而推进了多源能源应用的热泵技术。

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引用次数: 0

Heating performance analysis and operation optimization of CO2 secondary throttle heat pump system for electric vehicles 电动汽车CO2二次节流阀热泵系统供热性能分析及运行优化

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2025-12-09 DOI: 10.1016/j.ijrefrig.2025.12.008

Weijia Jiang , Ke Chen , Aikun Tang , Tao Cai , Shuangyuan Xiong , Zhikun Liu

To address the challenges of high energy consumption during winter heating and limited driving range in electric vehicles, a transcritical CO₂ secondary throttling heat pump system, which integrates an internal heat exchanger and dual expansion valves, is proposed in this study. By optimizing the dual indoor heat exchangers and a staged throttling, the refrigerant heat exchange efficiency of the system within the heating cycle is enhanced. A 1D thermal management simulation model incorporating both cabin and battery is first developed, whose accuracy is demonstrated to be quite satisfactory by comparing numerical results with experimental data. Subsequently, a comparative analysis between the secondary throttling system and a conventional heat pump reveals a heating capacity increase of 50.88 % at 0 °C. Further parametric studies are conducted under varying valve openings, indoor/outdoor airflow rates, and compressor speeds, demonstrating that the coordinated control of dual EXVs effectively regulates the intermediate pressure. Additionally, airflow parameters and compressor speed significantly influence overall system performance. Under optimized operating conditions, the system achieves significant improvements in both heating capacity and coefficient of performance, demonstrating the effectiveness of the proposed design. This investigation provides a viable technical pathway for optimizing CO₂ heat pump air conditioning systems.

针对电动汽车冬季采暖能耗高、续行驶里程有限的问题，提出了一种内置换热器和双膨胀阀的跨临界CO2二次节流热泵系统。通过优化室内双热交换器和分级节流，提高了系统在采暖周期内制冷剂的换热效率。首先建立了包括舱室和电池在内的一维热管理仿真模型，并将数值结果与实验数据进行了比较，结果表明该模型的精度令人满意。随后，对二次节流系统和传统热泵进行了对比分析，结果表明，在0°C时，二次节流系统的供热能力提高了50.88%。进一步的参数研究在不同的阀门开度、室内/室外气流速率和压缩机速度下进行，证明双exv的协调控制有效地调节了中间压力。此外，气流参数和压缩机转速显著影响系统的整体性能。在优化运行条件下，系统的供热能力和性能系数均有显著提高，证明了所提设计的有效性。本研究为优化CO2热泵空调系统提供了一条可行的技术途径。

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