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

Static magnetic field-assisted impregnation freezing improves crayfish quality: Insights into water mobility and ice crystal morphology 静磁场辅助浸渍冷冻提高小龙虾品质：洞察水的流动性和冰晶形态

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-02-27 DOI: 10.1016/j.ijrefrig.2026.02.032

Qiang Li , Yaokun Lu , Jianfeng Lu , Yuan Song , Zhicheng Cai , Beibei Zhou , Lin Lin , Wenhua Miao , Bin Zheng , Changhu Xue

This study aimed to investigate the effect of low-intensity (0, 2, 4, 6, 8 mT) static magnetic fields (SMF)-assisted impregnation freezing on crayfish quality during freezing. Results demonstrated that the application of SMF reduced freezing time by 7.6 % to 35.8 %. Microscopic analysis revealed that the ice crystals in the SMF treatment group were smaller and more uniformly distributed. Additionally, the water holding capacity of crayfish muscle improved after SMF treatment, with the 4 mT treatment group showing a 3.88 % increase compared to the immersion freezing after six weeks of storage. Texture analysis indicated that the 4 mT treatment group exhibited improved springiness and chewability of crayfish. Furthermore, pH levels in the SMF-treated group approached those of fresh samples more closely than the control group during frozen storage. Low-field nuclear magnetic resonance results showed shorter relaxation times in the SMF treatment group, indicating reduced molecular mobility during crayfish freezing. Moreover, the degree of damage to the fibrillar muscle tissue was lighter compared to the control group. The total sulfhydryl content in crayfish treated with 0, 2, 4, 6, and 8 mT decreased by 58.81 %, 39.22 %, 36.76 %, 46.66 %, and 56.63 %, respectively, after six weeks, suggesting that SMF treatment could delay protein oxidation. Mechanistically, SMF regulated water rearrangement to form uniform ice crystals, thereby minimizing mechanical damage to muscle tissue. In conclusion, SMF-assisted impregnation freezing effectively reduces water loss and delays quality deterioration of frozen crayfish, with the 4 mT treatment demonstrating the most significant impact.

本研究旨在研究低强度（0、2、4、6、8 mT）静磁场（SMF）辅助浸渍冷冻对冷冻过程中小龙虾品质的影响。结果表明，SMF的施用使冻结时间缩短了7.6% ~ 35.8%。显微分析显示，SMF处理组的冰晶更小，分布更均匀。此外，经过SMF处理后，小龙虾肌肉的持水能力有所提高，在6周的储存后，4 mT处理组比浸泡冷冻组增加了3.88%。质地分析表明，4 mT处理组小龙虾的弹性和咀嚼性有所改善。此外，在冷冻储存期间，smf处理组的pH值比对照组更接近新鲜样品的pH值。低场核磁共振结果显示，SMF处理组弛豫时间较短，表明小龙虾冷冻过程中分子迁移率降低。此外，与对照组相比，纤维性肌肉组织的损伤程度较轻。0、2、4、6和8 mT处理6周后，小龙虾的总巯基含量分别降低了58.81%、39.22%、36.76%、46.66%和56.63%，表明SMF处理可以延缓蛋白质氧化。在机械上，SMF调节水重排形成均匀的冰晶，从而最大限度地减少对肌肉组织的机械损伤。综上所述，smf辅助浸渍冷冻有效地减少了冷冻小龙虾的水分流失，延缓了冷冻小龙虾的品质劣化，其中4 mT处理效果最为显著。

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引用次数: 0

Cryoprotectant efficacy across fruit matrices: A comparative study of apples and grapes 低温保护剂在水果基质中的功效：苹果和葡萄的比较研究

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-02-27 DOI: 10.1016/j.ijrefrig.2026.02.031

Masitah Othman , Nurul Aini Amran , Wan Nur Aisyah Wan Osman , Haruna Adamu

The application of cryoprotectants is a promising strategy to mitigate freezing-induced quality deterioration in fresh-cut fruits; however, comparative evidence across fruit matrices and application strategies remains limited. This study systematically evaluated the cryoprotective efficacy of glycerol, sorbitol, and xylitol at 50 %, 75 %, and 100 % concentrations using two exposure strategies which are prolonged soaking and short-term dipping under aqueous and anhydrous conditions in Royal Gala apples and Shine Muscat grapes. Post-thaw quality was assessed in terms of morphological integrity, water loss, and soluble solid (Brix) retention. Across both fruits, soaking treatments resulted in substantial water loss, reaching 27.74–37.58 % in grapes and 48.79–63.77 % in apples, indicating pronounced osmotic dehydration. In contrast, dipping treatments significantly reduced water loss to below 2.5 % for grapes and below 5.2 % for apples, regardless of cryoprotectant type. Among the formulations, xylitol-based systems consistently outperformed glycerol and sorbitol, particularly at higher concentrations. For Shine Muscat grapes, 75–100 % xylitol dipping limited water loss to 1.86–2.17 %, while Royal Gala apples treated with 50 % xylitol dipping exhibited the lowest water loss (2.91 %) among all tested conditions. These treatments also preserved tissue firmness and maintained soluble solid content more effectively than glycerol-rich formulations. Overall, the findings demonstrate that xylitol-dominant, anhydrous dipping protocols provide superior cryoprotection across fruits with contrasting cellular structures, offering a scalable, clean-label strategy for improving frozen fruit quality and stability.

低温保护剂的应用是一种很有前途的策略，以减轻冷冻引起的鲜切水果品质劣化；然而，水果基质和应用策略之间的比较证据仍然有限。本研究系统地评估了甘油、山梨醇和木糖醇在50%、75%和100%浓度下的冷冻保护效果，采用两种暴露策略，即在水和无水条件下长时间浸泡和短期浸泡。解冻后的质量是根据形态完整性、失水和可溶性固形物（Brix）保留来评估的。在两种水果中，浸泡处理导致大量水分流失，葡萄达到27.74 - 37.58%，苹果达到48.79 - 63.77%，表明明显的渗透脱水。相比之下，无论冷冻保护剂类型如何，浸渍处理显著降低了葡萄和苹果的水分损失率，分别低于2.5%和5.2%。在配方中，木糖醇为基础的系统始终优于甘油和山梨醇，特别是在较高浓度下。对于Shine Muscat葡萄，75% ~ 100%木糖醇浸出的水分流失率限制在1.86 ~ 2.17%，而50%木糖醇浸出的Royal Gala苹果在所有试验条件下的水分流失率最低（2.91%）。与富含甘油的配方相比，这些处理还能更有效地保持组织的硬度和可溶性固形物含量。总的来说，研究结果表明，木糖醇为主的无水浸渍方案在具有不同细胞结构的水果中提供了优越的冷冻保护，为提高冷冻水果的质量和稳定性提供了可扩展的清洁标签策略。

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引用次数: 0

Model-experiment-hybrid optimization of refrigerant charge via iterative calibration for a pilot vapor compression system 中试蒸汽压缩系统制冷剂充注迭代标定模型-实验-混合优化

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-03-05 DOI: 10.1016/j.ijrefrig.2026.106895

Zi-Yang Zhang , Chun-Lu Zhang

Refrigerant charge optimization is critical for maximizing efficiency of vapor compression refrigeration and heat pump systems. Conventional multi-step charging experiments determine the optimal charge with high accuracy but are resource-intensive. In contrast, model-based approaches can reduce the experimental burden yet show limited practical effectiveness due to relatively large prediction errors. To tackle these limitations, this paper proposes a model-experiment-hybrid method for refrigerant charge optimization. The approach is founded on the key insight that the optimal subcooling can be reliably predicted by a calibrated system model, whereas the specific refrigerant charge inventory is highly sensitive to void fraction uncertainties. Therefore, the proposed method utilizes experimental feedback to iteratively calibrate the system model. This allows the model to predict optimal subcooling and calculate the iterative charge step size based on subcooling deviations, effectively minimizing reliance on void fraction correlations. Experimental validation under three conditions demonstrates that the method accurately obtains the optimal COP for a pilot vapor compression system. The differences in optimal charge between the conventional method and the proposed method are within 0.05 kg while the deviations of optimal subcooling are <0.4 K. The proposed hybrid method converges to optimal charge within two iterations, regardless of the void fraction correlation used, and achieves an average reduction in experimental workload of 58% compared to the conventional method. The model-experiment-hybrid optimization of refrigerant charge method effectively decouples charge optimization accuracy from void fraction model errors, offering a promising solution in refrigeration and heat pump product development.

制冷剂充注优化是蒸汽压缩制冷和热泵系统效率最大化的关键。传统的多步充电实验确定最优充电量精度高，但耗费大量资源。相比之下，基于模型的方法可以减少实验负担，但由于预测误差较大，实际效果有限。针对这些局限性，本文提出了一种模型-实验-混合的制冷剂充注优化方法。该方法建立在通过校准系统模型可以可靠地预测最佳过冷度的关键见解之上，而特定制冷剂充注量对空隙率的不确定性高度敏感。因此，该方法利用实验反馈对系统模型进行迭代标定。这使得该模型能够预测最佳过冷度，并根据过冷度偏差计算迭代电荷步长，有效地减少了对空隙率相关性的依赖。三种工况下的实验验证表明，该方法准确地获得了先导蒸汽压缩系统的最优COP。该方法与传统方法的最佳电荷差值在0.05 kg以内，最佳过冷度偏差在0.4 K以内。所提出的混合方法在两次迭代内收敛到最优电荷，而不考虑使用的空隙率相关性，并且与传统方法相比，平均减少了58%的实验工作量。制冷剂充注量模型-实验-混合优化方法有效地将充注量优化精度与空隙率模型误差解耦，为制冷和热泵产品开发提供了一种有前景的解决方案。

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引用次数: 0

Design method and parameters optimization of finned-tube latent thermal energy storage for heat pump applications 热泵用翅片管潜热蓄能器设计方法及参数优化

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-02-23 DOI: 10.1016/j.ijrefrig.2026.02.025

Shengqi Zhang , Wanchun Hu , Guangdi Liu , Liang Pu

This study employs a finned-tube heat exchanger as the heat-exchange core and modified Sodium acetate trihydrate (SAT) as the storage medium to design a 6.0 kWh finned-tube latent thermal energy storage (FT-LTES) unit and investigate performance enhancement via geometric optimization. The modified SAT was subjected to 2000 thermal cycles. Compared with the initial state, the latent heat decreased by 7.0%, while the degree of supercooling increased by 9.2 °C. A 3D transient computational model, integrating shell conduction theory with phase change dynamics, was developed to systematically evaluate five geometric parameters: fin thickness, fin spacing, tube diameter, horizontal tube spacing and vertical tube spacing. The discharging performance was evaluated based on the key metrics: effective discharging time, average discharging power and effective water supply volume. The results reveal that, within the studied parameter range, the effective discharging capacity of the FT-LTES module increases with greater fin thickness, smaller fin spacing, and reduced tube spacing, while exhibiting a non-monotonic relationship with tube diameter, initially increasing and then decreasing. An optimized structure for the FT-LTES unit was identified, with fin thickness, fin spacing, horizontal tube spacing, vertical tube spacing, and tube diameter of 0.2 mm, 1.9 mm, 12.0 mm 16.0 mm and 25.4 mm, respectively. Multi-cycle thermal storage and release tests on the optimized structure demonstrated 128.0% improvement in effective water supply volume compared to the original LTES unit.

本研究以翅片管换热器为换热核心，以改性三水合乙酸钠（SAT）为存储介质，设计了6.0 kWh的翅片管潜热储能（FT-LTES）装置，并通过几何优化研究其性能增强。改进后的SAT经受了2000次热循环。与初始状态相比，潜热降低了7.0%，过冷度提高了9.2℃。将壳传导理论与相变动力学相结合，建立了三维瞬态计算模型，对翅片厚度、翅片间距、管径、水平管间距和垂直管间距5个几何参数进行了系统评价。根据有效排放时间、平均排放功率和有效供水量等关键指标对其排放性能进行评价。结果表明：在所研究的参数范围内，FT-LTES模块的有效放电容量随翅片厚度增大、翅片间距减小和管间距减小而增大，与管径呈先增大后减小的非单调关系；确定了FT-LTES装置的优化结构，翅片厚度为0.2 mm，翅片间距为1.9 mm，水平管间距为12.0 mm，垂直管间距为16.0 mm，管径为25.4 mm。优化结构的多循环蓄放热试验表明，与原LTES机组相比，有效供水量提高了128.0%。

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引用次数: 0

Experimental study of an R515B/CO2 cascade refrigeration system for commercial applications 商用R515B/CO2级联制冷系统的实验研究

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-03-09 DOI: 10.1016/j.ijrefrig.2026.106901

Bingdong Wang, Yaoxiang Han, Lixin Liu, Yanpeng Li, Chuang Wang, Ziwen Xing

CO₂ has been recognized as an ideal refrigerant for the low-temperature cycle (LTC) in a commercial cascade refrigeration system (CRS). Against the backdrop of global warming, low-GWP refrigerant substitution for the high-temperature cycle (HTC) is becoming increasingly critical, and R515B is regarded as a promising solution. In this paper, an R515B/CO₂ CRS experimental setup is constructed to comprehensively evaluate the system performance under various operating conditions. Moreover, performance variations of the refrigeration compressors in the LTC and HTC are also tested and analyzed. According to the results, the LTC performance is primarily governed by the intermediate and evaporating temperatures, remaining relatively insensitive to the condensing temperature. In contrast, the HTC performance exhibits high sensitivity to the condensing temperature. Consequently, increasing the condensing temperature substantially raises the power consumption of the HTC compressor and leads to a marked decline in the system coefficient of performance (COP_sys). The analysis also confirms the existence of an optimal intermediate temperature. Under typical operating conditions with a condensing temperature of 40°C and an evaporating temperature of −23°C, the system achieves a maximum COP_sys of 1.74. Furthermore, the R515B/CO₂ system demonstrates superior thermodynamic performance compared to similar CRSs utilizing high-GWP refrigerants as reported in the literature. Specifically, at an evaporating temperature of -30°C and a condensing temperature of 40°C, the system achieves a COP_sys of 1.48, representing an improvement of approximately 4.2% over the best-reported R134a/CO₂ CRS under identical conditions. From a life-cycle environmental perspective, the total equivalent warming impact of the R515B/CO₂ CRS is also reduced by approximately 15.0% compared to the R134a/CO₂ CRS. Coupled with its A1 safety classification and low GWP, R515B proves to be a highly promising HTC refrigerant for commercial CRSs.

CO2已被公认为商业级联制冷系统（CRS）中低温循环（LTC）的理想制冷剂。在全球变暖的背景下，低gwp制冷剂替代高温循环（HTC）变得越来越重要，R515B被认为是一个有前途的解决方案。本文搭建了R515B/CO2 CRS实验装置，综合评价了系统在各种工况下的性能。此外，还对LTC和HTC制冷压缩机的性能变化进行了测试和分析。结果表明，LTC的性能主要受中间温度和蒸发温度的影响，对冷凝温度相对不敏感。相比之下，HTC的性能表现出对冷凝温度的高灵敏度。因此，提高冷凝温度会大大提高HTC压缩机的功耗，并导致系统性能系数（COPsys）明显下降。分析还证实了最优中间温度的存在。在冷凝温度为40℃，蒸发温度为- 23℃的典型工况下，系统最大COPsys为1.74。此外，与文献中报道的使用高gwp制冷剂的类似CRSs相比，R515B/CO2系统表现出优越的热力学性能。具体来说，在蒸发温度为-30°C，冷凝温度为40°C时，该系统的COPsys为1.48，比同等条件下报道的最佳R134a/CO2 CRS提高了约4.2%。从生命周期环境的角度来看，R515B/CO2 CRS的总等效变暖影响也比R134a/CO2 CRS减少了约15.0%。再加上其A1安全等级和低GWP， R515B被证明是一种非常有前途的商用CRSs HTC制冷剂。

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引用次数: 0

Where and how to place the injection structure of a cascade high-temperature heat pump with large-temperature differences: A comprehensive analysis 大温差叶栅高温热泵的喷射结构放置在何处，如何放置：综合分析

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-02-26 DOI: 10.1016/j.ijrefrig.2026.02.029

Lingxiao Yang , Xin Wang , Bo Xu , Zhenqian Chen

In the context of utilizing cascade high-temperature heat pumps (HTHPs) for heating applications with large-temperature differences, the optimal placement and implementation of the injection structure continue to present an unresolved issue. To this end, this paper develops two otherwise-identical cascade HTHP configurations: the HT-VIE-CS with the injection structure placed in the high-temperature stage and the LT-VIE-CS with the structure placed in the low-temperature stage. Subsequently, performance and stability are compared over wide ambient temperature (T_am) and heating temperature (T_h) ranges, and several refrigerant pairs are screened. Results show that placing the injection structure in the low-temperature stage generally increases heating COP, with a maximum advantage of 4.0 % over HT-VIE-CS in the investigated conditions, while HT-VIE-CS retains a larger stability margin. Across refrigerant pairs, LT-injection remains favorable, and R152a/R245ca provides the best overall trade-off. Based on the stability-performance balance, a flexible selection strategy is proposed: as T_am rises, the recommended configuration shifts from HT-VIE-CS to LT-VIE-CS and then to a simpler two-stage injection system, with transition T_am of -1/5/10°C and 48/56/64°C for T_h = 120/130/140°C, respectively. A techno-economic and carbon assessment indicates that under current conditions, when T_am > 3°C, its operating costs are lower than those of gas boilers, and when T_am > 24°C, its emissions are lower than those of coal boilers.

在利用级联高温热泵（HTHPs）进行大温差加热应用的背景下，喷射结构的最佳放置和实施仍然是一个未解决的问题。为此，本文开发了两种完全相同的叶栅高温高压配置：ht - viev - cs注入结构位于高温段，lt - viev - cs结构位于低温段。随后，在较宽的环境温度（Tam）和加热温度（Th）范围内比较性能和稳定性，并筛选几种制冷剂对。结果表明，将注入结构置于低温阶段通常会增加加热COP，在所研究的条件下，其最大优势比HT-VIE-CS高4.0%，而HT-VIE-CS保持更大的稳定裕度。在制冷剂对中，lt喷射仍然是有利的，R152a/R245ca提供了最佳的整体权衡。基于稳定性与性能的平衡，提出了一种灵活的选择策略：随着Tam的升高，推荐配置从HT-VIE-CS转向LT-VIE-CS，然后转向更简单的两级喷射系统，Th = 120/130/140°C时，过渡Tam分别为-1/5/10°C和48/56/64°C。技术经济和碳评价表明，在目前条件下，当Tam >； 3℃时，其运行成本低于燃气锅炉，当Tam >； 24℃时，其排放低于燃煤锅炉。

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引用次数: 0

Numerical simulation of conjugate heat transfer in pre-cooling process of cryogenic propellant transfer line by cryocoolers 低温推进剂输送管线预冷过程中低温制冷机共轭传热的数值模拟

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-02-26 DOI: 10.1016/j.ijrefrig.2026.02.027

Xi Lai , Jianghan Chen , Dier Ma , Ziying Luo , Shiran Bao , Limin Qiu , Kai Wang , Xiaoqin Zhi

In response to the instability of two-phase flow, the challenges regarding precise prediction and control, and the significant fluid loss during the quenching of cryogenic propellant pipes, this study introduces a dry pre-cooling process based on cryocoolers. Leveraging the high stability, compactness, and reliability of cryocooler technology-which has demonstrated significant value in applications such as superconducting magnet coils and space infrared telescopes—this work aims to enhance the stability, controllability, and safety of the filling pipe pre-cooling process. Based on the structural features of the aerospace filling pipe and the operational characteristics of cryocoolers, four pre-cooling methods are presented: the external circulation method, the internal circulation method, the copper thermal straps method, and the built-in fin method. A three-dimensional numerical model of the cryocooler-pipe system was developed to simulate conjugate heat transfer during the pre-cooling process. Additionally, the effects of flow rate on the pre-cooling process were investigated, and the cooling performance of various methods was compared and assessed. The results indicated that the internal circulation method achieved the shortest cooling time of 459 min and the highest cooling efficiency of 89.2%. In terms of temperature uniformity, the external circulation method exhibited superior performance, followed by the internal circulation method. This study is anticipated to improve the controllability and reliability of cryogenic propellant pipe pre-cooling, providing technical support for the safe implementation of large-scale and high-frequency space missions in the future.

针对低温推进剂管道淬火过程中两相流动的不稳定性、预测和控制精度的挑战以及流体损失大等问题，提出了一种基于制冷机的干式预冷工艺。利用制冷机技术的高稳定性、紧凑性和可靠性，该技术在超导磁体线圈和空间红外望远镜等应用中显示出重要价值，本工作旨在提高灌装管预冷过程的稳定性、可控性和安全性。根据航天加注管的结构特点和制冷机的工作特点，提出了四种预冷方法：外循环法、内循环法、铜热带法和内置翅片法。为了模拟预冷过程中的共轭传热，建立了低温冷却器-管道系统的三维数值模型。此外，还研究了流量对预冷过程的影响，并对不同预冷方式的冷却性能进行了比较和评价。结果表明，内循环冷却时间最短，为459 min，冷却效率最高，为89.2%。在温度均匀性方面，外循环法表现较好，内循环法次之。该研究有望提高低温推进剂管道预冷的可控性和可靠性，为未来大规模、高频空间任务的安全实施提供技术支撑。

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引用次数: 0

Experimental study on a heat pump-boosted closed-cycle desiccant wheel system in deep mine 深部矿井热泵驱动闭式循环干燥剂轮系统试验研究

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-03-02 DOI: 10.1016/j.ijrefrig.2026.106892

Yujie Xu , Liu Chen , Yue Liu , Zhenyuan Guo

Deep mine heat damage critically threatens mining safety, whereas traditional cooling systems suffer from high energy consumption and inadequate dehumidification. To address these issues, a heat pump-boosted closed-cycle desiccant wheel system (HP-CDWS) is proposed, which uses water source heat pump (WSHP) and desiccant wheel system to achieve deep cooling and dehumidification of mine airflow. The evaporator provides chilled water for precooling of mine airflow, and the condenser supplies hot water to heat the regeneration air of the desiccant wheel with purge sector (DW-PS). Condensation dehumidification is used to pre-dehumidify the mine airflow, and DW-PS is used for further deep dehumidification to obtain low air humidity ratio. An experimental platform is built and used to test the performance of the HP-CDWS. The results show that increasing the mine airflow inlet temperature from 28 °C to 38 °C boosts the thermal coefficient of performance (TCOP), moisture removal capacity (MRC), and exergy efficiency by 93.3%, 84.0%, and 11.8%, respectively; higher mine airflow inlet relative humidity (70–95%) increases TCOP and MRC by 29% and 27%, respectively, but reduces exergy efficiency by 21.2%; elevating regeneration temperature (50–100 °C) increases MRC by 29% while decreasing TCOP and exergy efficiency by 51.4% and 6.9%, respectively. Compared with traditional systems, the HP-CDWS achieves a 5.2-year payback period and 4.8% lower life cycle cost, proving an energy-efficient and economically viable solution.

矿井深部热损伤严重威胁着矿山安全，而传统冷却系统存在能耗高、除湿能力差等问题。针对这些问题，提出了热泵增压闭式循环干燥剂轮系统（HP-CDWS），该系统利用水源热泵和干燥剂轮系统实现矿井气流的深度冷却和除湿。蒸发器提供冷冻水用于矿井气流的预冷，冷凝器提供热水用于加热带吹扫扇区（DW-PS）的干燥剂轮的再生空气。采用冷凝除湿对矿井气流进行预除湿，采用DW-PS进行进一步深度除湿，以获得较低的空气湿度比。搭建了实验平台，对HP-CDWS的性能进行了测试。结果表明：将矿井进风温度由28℃提高到38℃时，热工系数（TCOP）、除湿能力（MRC）和火用效率分别提高了93.3%、84.0%和11.8%；较高的矿井气流进口相对湿度（70 ~ 95%）使TCOP和MRC分别提高29%和27%，但使火用效率降低21.2%；提高再生温度（50 ~ 100℃）可使MRC提高29%，而TCOP和火用效率分别降低51.4%和6.9%。与传统系统相比，HP-CDWS的投资回收期为5.2年，生命周期成本降低4.8%，是一种节能且经济可行的解决方案。

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引用次数: 0

Physics-informed acoustic leak detection in R32 multi-split systems via evolutionary machine learning 基于进化机器学习的R32多分裂系统物理信息声学泄漏检测

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-06-01 Epub Date: 2026-02-28 DOI: 10.1016/j.ijrefrig.2026.02.030

Xiaoyu Ma, Zhao Yang, Xueling Liu, Yiping Wang

The transition to flammable R32 refrigerant requires rapid and interpretable leak detection. Traditional acoustic diagnostics frequently fail under non-stationary conditions because they overlook the effect of Oil Circulation Rate (OCR) fluctuations on acoustic source mechanisms. A decrease in OCR shifts the flow regime from oil-film-damped two-phase flow to a high-frequency, turbulence-dominated pure gas jet. This phase transition and the resulting spectral drift compromise models trained on steady-state features. We propose a hierarchical framework that integrates multi-objective feature selection with explainable machine learning. Using an acoustic database covering the evolution from normal circulation to oil-depleted states, an improved ensemble NSGA-II algorithm identifies 15 features insensitive to oil content variations. A Triangular Topology Aggregation Optimizer then tunes Support Vector Machine hyperparameters. The model achieves 31.8% dimensionality reduction and 97.27% accuracy, mitigating recognition errors caused by OCR fluctuations. A recall rate exceeding 94% is maintained for near-field micro-leaks, enabling alerts before refrigerant accumulation reaches the Lower Flammability Limit (LFL). SHAP analysis demonstrates consistency between model decisions and the physics of acoustic attenuation and fluid phase transitions, offering a physically interpretable solution for HVAC safety monitoring.

过渡到易燃的R32制冷剂需要快速和可解释的泄漏检测。由于忽略了油循环速率（OCR）波动对声源机制的影响，传统的声学诊断在非平稳条件下经常失败。OCR的降低使流态从油膜阻尼的两相流转变为高频、湍流主导的纯气体射流。这种相变和由此产生的光谱漂移损害了在稳态特征上训练的模型。我们提出了一个将多目标特征选择与可解释机器学习相结合的分层框架。利用涵盖从正常循环到缺油状态演变的声学数据库，改进的集合NSGA-II算法识别出15个对含油量变化不敏感的特征。然后，三角拓扑聚合优化器调整支持向量机超参数。模型降维率达到31.8%，准确率达到97.27%，缓解了OCR波动带来的识别误差。近场微泄漏的召回率超过94%，能够在制冷剂积累达到低可燃性限值（LFL）之前发出警报。SHAP分析证明了模型决策与声学衰减和流体相变的物理特性之间的一致性，为暖通空调安全监测提供了物理上可解释的解决方案。

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引用次数: 0

Cryoprotective effects of glycerol on the structure and function of myofibrillar proteins in pork patties with multiple freeze-thaw cycles 甘油对多次冻融循环猪肉肉饼中肌原纤维蛋白结构和功能的冷冻保护作用

IF 3.8 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2026-05-01 Epub Date: 2026-01-27 DOI: 10.1016/j.ijrefrig.2026.01.035

Huihui Liang , Xun Gao , Yunyun Jiang , Xiaoxu Zhu , Cunliu Zhou

This study investigated the cryoprotective effects of glycerol on myofibrillar proteins (MPs) in pork patties subjected to repeated freeze–thaw cycles. Compared with the control, glycerol markedly inhibited the reduction in protein solubility and absolute zeta potential while suppressing the increase in turbidity and average particle size of MPs. It effectively delayed the increase of carbonyl group and surface hydrophobicity, the decline in total sulfhydryl groups and intrinsic fluorescence intensity, and the conformational transition from α-helix to β-sheet. Glycerol also mitigated the loss of whiteness, textural strength, and intermolecular interactions and retarded the thermal denaturation of MP molecules. Moreover, it reduced cooking loss and microstructural degradation in MP gels. In emulsification systems, glycerol alleviated the decline in emulsifying activity and stability, limited the increase in creaming index, and prevented oil droplet coalescence in MP–soybean oil emulsions. Overall, glycerol preserved the gelation and emulsification functionality of MPs by delaying protein aggregation and conformational disruption, thereby maintaining the structural integrity and quality of pork patties during multiple freeze–thaw cycles.

本研究研究了甘油对反复冻融循环的猪肉肉饼中肌原纤维蛋白（MPs）的冷冻保护作用。与对照组相比，甘油显著抑制了蛋白溶解度和绝对zeta电位的降低，同时抑制了MPs的浊度和平均粒径的增加。它有效地延缓了羰基和表面疏水性的增加，总巯基和本征荧光强度的下降，以及α-螺旋向β-片的构象转变。甘油还减轻了白度、结构强度和分子间相互作用的损失，并延缓了MP分子的热变性。此外，它还减少了MP凝胶的蒸煮损失和微结构降解。在乳化体系中，甘油缓解了乳化活性和稳定性的下降，限制了成乳指数的增加，阻止了mp -豆油乳剂中的油滴聚结。总的来说，甘油通过延缓蛋白质聚集和构象破坏来保持MPs的凝胶化和乳化功能，从而在多次冻融循环中保持猪肉肉饼的结构完整性和质量。

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引用次数: 0