International Journal of Refrigeration-revue Internationale Du Froid最新文献_第2页

Achieving off-grid refrigeration in remote areas: A solar-powered vapor compression refrigerator prototype with PCM integration 在偏远地区实现离网制冷：集成 PCM 的太阳能蒸汽压缩冰箱原型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-30 DOI: 10.1016/j.ijrefrig.2024.10.028

Angelo Maiorino , Fabio Petruzziello , Arcangelo Grilletto , Claudio Cilenti , Ciro Aprea

The availability of vaccines, medicines, and perishable goods in remote or off-grid areas remains a formidable challenge. Integrating solar photovoltaic (PV) systems with refrigeration technology has emerged as a promising solution to address this critical need. This paper presents an autonomous solar-powered refrigerator prototype for off-grid refrigeration in remote areas utilising renewable energy. The system comprises a 160 W photovoltaic module, a 12/24 V DC compressor refrigerator, a lead-acid battery, and a Maximum Power Point Tracking (MPPT) controller. Its main feature is complete autonomy from the electricity grid, thanks to its standalone configuration. An experimental campaign evaluated the system's behaviour in the laboratory for 24 h at different set-point temperatures. A water-based Phase Change Material (PCM) was implemented to improve its autonomy in severe outdoor conditions. A further experimental campaign emulated the functioning of the prototype while managing the temperature of a sample solution whose melting temperature was equal to – 21 °C to ensure its liquid state during the tests. The target range for preserving the sample was defined at ± 1 °C. Several real conditions have been considered, such as higher cooling loads realised through 21 litres of additional thermal mass in the refrigerator and pick and place conditions for simulating the opening and closing of the door. The results demonstrate that the solar refrigerator prototype achieves complete autonomy from the electricity grid, paving the way for solutions for preserving perishable goods such as medicines and food in unelectrified areas.

在偏远或离网地区提供疫苗、药品和易腐物品仍然是一项艰巨的挑战。将太阳能光伏（PV）系统与制冷技术相结合，已成为满足这一关键需求的一个前景广阔的解决方案。本文介绍了一种利用可再生能源在偏远地区进行离网制冷的自主太阳能冰箱原型。该系统由一个 160 W 光伏模块、一个 12/24 V 直流压缩机冰箱、一个铅酸电池和一个最大功率点跟踪 (MPPT) 控制器组成。该系统的主要特点是独立配置，完全脱离电网。一项实验活动评估了该系统在实验室中不同设定温度下 24 小时的运行情况。系统采用了水基相变材料 (PCM)，以提高其在恶劣室外条件下的自主性。另一项实验活动是模拟原型的功能，同时管理样品溶液的温度，该溶液的熔化温度等于 - 21 °C，以确保其在测试期间处于液态。样品保存的目标范围为 ± 1 °C。试验考虑了一些实际条件，例如通过在冰箱中增加 21 升热量来实现更高的制冷负荷，以及模拟开关门的取放条件。结果表明，太阳能冰箱原型实现了完全脱离电网，为在无电地区保存药品和食品等易腐物品的解决方案铺平了道路。

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引用次数: 0

Effect of different freezing temperatures on the physical, technological, and organoleptic properties of aged semimembranosus muscles from farmed fallow deer (Dama dama) 不同冷冻温度对养殖坡鹿（Dama dama）陈年半膜肌肉的物理、技术和感官特性的影响

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-28 DOI: 10.1016/j.ijrefrig.2024.10.029

Eva Kudrnáčová , Tersia Kokošková , Nicole Lebedová , Daniel Bureš

Although venison could play an important role in human nutrition, this meat remains undervalued and still contributes very little to the formal meat industry. Moreover, information on processing methods of fallow deer meat and overall quality is still very limited. The objective of this study was to determine how physical, technological, and organoleptic properties differ between 14-day-aged vacuum-packaged fallow deer meat stored either chilled or frozen at different temperatures (-10 °C, -18 °C, -40 °C and -80 °C) for six months. Physical, technological, and organoleptic analyses were conducted on semimembranosus muscles (SM) obtained from farmed fallow deer bucks (n= 10). Freezing significantly increased meat redness, yellowness, chroma values, cooking loss and tenderness compared to fresh meat but did not affect pH values, lightness, thawing, or grilling loss. Mean pH readings were 5.5–5.6, being highest in the samples measured one day after slaughter. Freezing at -80 °C had the most pronounced effect on some sensory attributes, namely, the highest game meat aroma intensity, sour odour, sour flavour and the lowest chewiness. The findings indicate that a freezing temperature of -18 °C and subsequent slow thawing might be preferential in terms of maintaining fallow deer meat quality.

尽管鹿肉在人类营养中可以发挥重要作用，但这种肉类的价值仍然被低估，对正规肉类产业的贡献仍然很小。此外，有关鹿肉加工方法和整体质量的信息仍然非常有限。本研究的目的是确定在不同温度（-10 °C、-18 °C、-40 °C和-80 °C）下冷藏或冷冻保存 6 个月的 14 天真空包装鹿肉的物理、技术和感官特性有何不同。对从养殖的野鹿（10 头）身上获取的半膜肌（SM）进行了物理、技术和感官分析。与鲜肉相比，冷冻会明显增加肉的红度、黄度、色度值、烹饪损失和嫩度，但不会影响 pH 值、亮度、解冻或烧烤损失。平均 pH 值为 5.5-5.6，屠宰后一天测量的样本 pH 值最高。零下 80 摄氏度的冷冻温度对某些感官属性的影响最为明显，即野味肉的香气强度、酸臭味和酸味最高，咀嚼感最低。研究结果表明，-18 °C的冷冻温度和随后的缓慢解冻可能更有利于保持秋鹿肉的品质。

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引用次数: 0

Experimental study on hydraulic performance and cavitation characteristics of a R134a refrigerant self-lubricating centrifugal pump R134a 制冷剂自润滑离心泵的水力性能和气蚀特性试验研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-28 DOI: 10.1016/j.ijrefrig.2024.10.027

Ze Zhang , Song Yang , Beile Zhang , Xufeng Fang , Rong Xue , Shuangtao Chen , Yu Hou

As the primary power equipment in pump flooding cooling systems, the efficiency and performance of mechanical pumps play a crucial role in two-phase cooling systems. A high-speed centrifugal pump with self-lubricating working fluid was designed with a speed of 7500 rpm and a flow coefficient of 0.0506. The hydraulic and cavitation performance of the pump were tested with R134a as the working fluid. The results show that the working fluid pump is capable of efficiently pumping R134a with an efficiency of 40.3 % and a head coefficient of 0.988 under the design condition. Within the tested range of inlet temperature from 5°C to 15°C, the flow coefficient from 0.01 to 0.105, and the height of the refrigerant tank from 1.4 m to 5 m, lower net positive suction heads available at the same flow rate will reduce the pump head, increase power consumption, and decrease efficiency. Increasing the pump speed from 3000 rpm to 7500 rpm can improve the pump's performance. At 6000 rpm, the critical cavitation number of the working fluid pump increases with the increase in flow coefficient. At 7500 rpm, the critical cavitation number has a minimum value when the flow coefficient φ = 0.0434. At the design speed and flow rate, both the critical cavitation coefficient and fracture cavitation number increase as the inlet temperature decreases. The inducer can significantly reduce the critical cavitation number of the pump. Finally, an empirical correlation considering the thermodynamic effects is proposed to predict the increase in the critical cavitation number.

作为泵淹没冷却系统的主要动力设备，机械泵的效率和性能在两相冷却系统中起着至关重要的作用。设计了一种带有自润滑工作流体的高速离心泵，转速为 7500 rpm，流量系数为 0.0506。以 R134a 为工作流体，对泵的水力和气蚀性能进行了测试。结果表明，在设计条件下，工作流体泵能够有效地泵送 R134a，效率为 40.3%，扬程系数为 0.988。在入口温度为 5°C 至 15°C、流量系数为 0.01 至 0.105、制冷剂罐高度为 1.4 米至 5 米的测试范围内，相同流量下的净正吸入扬程越低，泵的扬程越小，功耗越大，效率越低。将泵的转速从 3000 rpm 提高到 7500 rpm 可以提高泵的性能。在转速为 6000 rpm 时，工作流体泵的临界汽蚀数会随着流量系数的增加而增加。在 7500 rpm 时，当流量系数 φ = 0.0434 时，临界汽蚀数达到最小值。在设计转速和流量下，临界汽蚀系数和断裂汽蚀数都会随着入口温度的降低而增加。诱导器可大大降低泵的临界汽蚀数。最后，提出了一种考虑热力学效应的经验相关性来预测临界汽蚀数的增加。

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引用次数: 0

Advanced model for a non-adiabatic capillary tube considering both subcooled liquid and non-equilibrium two-phase states of R-600a 考虑到 R-600a 过冷液体和非平衡两相状态的非绝热毛细管高级模型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-28 DOI: 10.1016/j.ijrefrig.2024.10.031

Seongjun Jeon , Jaedeok Ko , Hyoin Lee , Ji Hwan Jeong

Previous empirical correlations have largely failed to predict the mass flow rate variations of R-600a during the transient pull-down operation of household refrigerators. This shortcoming is attributed to the fact that these correlations were developed for specific thermodynamic states of the refrigerant at the capillary inlet, whereas the thermodynamic state varies during transient operations, particularly involving non-equilibrium two-phase states. To address these limitations, a novel model has been developed. This model comprises two distinct sub-models corresponding to the refrigerant state at the capillary tube inlet: one for the subcooled liquid state and the other for the non-equilibrium two-phase state. These sub-models are integrated to account for the transitions in the thermodynamic state of R-600a at the capillary inlet. The integrated model demonstrates excellent agreement with observed variations in the R-600a mass flow rate during the pull-down operation of actual refrigerators. The mean absolute percentage error between the measured and estimated mass flow rates is approximately 10 % over the entire period of pull-down operations tested under various environmental conditions.

以前的经验相关性在很大程度上无法预测 R-600a 在家用冰箱瞬态下拉运行过程中的质量流量变化。造成这一缺陷的原因是，这些相关性是针对毛细管入口处制冷剂的特定热力学状态开发的，而在瞬态运行期间，热力学状态会发生变化，特别是涉及非平衡两相状态时。为了解决这些局限性，我们开发了一种新型模型。该模型由两个不同的子模型组成，分别对应毛细管入口处的制冷剂状态：一个是过冷液态，另一个是非平衡两相状态。对这些子模型进行了整合，以说明 R-600a 在毛细管入口处的热力学状态的转变。综合模型与实际冰箱在下拉运行过程中观察到的 R-600a 质量流量变化非常吻合。在各种环境条件下测试的整个下拉操作期间，测量质量流量和估计质量流量之间的平均绝对百分比误差约为 10%。

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引用次数: 0

Research and thermal comfort analysis of the air conditioning system of the Ferris wheel car based on thermoelectric cooling 基于热电冷却的摩天轮轿厢空调系统研究与热舒适性分析

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-28 DOI: 10.1016/j.ijrefrig.2024.10.030

Huizhi Li , Kuansheng Huang , Jiahui Liu , Mingjing Zhu , Jinchao Xing

To solve the problem of thermal discomfort caused by the lack of cooling facilities on the Ferris wheel and to investigate the effect of the coupling effect of thermoelectric modules on the thermoelectric cooling (TEC) system, this paper proposes a two-module thermoelectric cooling and air-conditioning system that can be applied to the Ferris wheel. Firstly, the experimental platform was established to test the performance parameters of the TEC system and reveal the influence of the thermoelectric module (TEM) coupling effect on the system performance. Then, the thermal environment inside the Ferris wheel was simulated using the CFD method and human thermal comfort was evaluated. The results show that when the voltage of TEM1 and TEM2 is 10 V and 6 V respectively, the thermoelectric cooling and air-conditioning system has the best working performance, and the coefficient of performance (COP) is 0.43. And the human thermal comfort deviation A_EQT is 0.29, which is in a comfortable state under the action of the air-conditioning system.

为解决摩天轮因缺乏制冷设施而产生的热不适问题，并研究热电模块耦合效应对热电制冷（TEC）系统的影响，本文提出了一种可应用于摩天轮的双模块热电制冷空调系统。首先，建立了实验平台来测试 TEC 系统的性能参数，并揭示了热电模块（TEM）耦合效应对系统性能的影响。然后，利用 CFD 方法模拟了摩天轮内部的热环境，并对人体热舒适度进行了评估。结果表明，当 TEM1 和 TEM2 的电压分别为 10 V 和 6 V 时，热电半导体制冷空调系统的工作性能最佳，性能系数（COP）为 0.43。人体热舒适度偏差 AEQT 为 0.29，在空调系统的作用下处于舒适状态。

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引用次数: 0

Quantitative detection of refrigerant charge faults in multi-unit air conditioning systems based on machine learning algorithms 基于机器学习算法的多单元空调系统制冷剂充注故障定量检测

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-26 DOI: 10.1016/j.ijrefrig.2024.10.026

Tong Zhao, Junhong Yang, Junda Zhu, Mengbo Peng, Can Lu, Zekun Shi

Refrigerant charging discrepancies constitute the predominant malfunctions in air conditioning systems. Achieving the optimal charging level is crucial for system performance, underscoring the importance of precise refrigerant level prediction. This study introduces an algorithm designed for the quantitative detection of refrigerant charging errors by integrating the Markov Transition Field (MTF), Convolutional Neural Networks (CNN), and Multi-head Self-Attention (MSA) mechanisms. A high-precision enthalpy difference chamber was employed to establish a Variable Refrigerant Flow (VRF) refrigerant charging test bench. This setup facilitated the analysis of system parameter sensitivity to charging faults and aided in the creation of a training dataset for the algorithm. Comparative analysis was conducted against Support Vector Machines (SVM), Random Forests (RF), CNN with Self-Attention (AT), and MTF-CNN-MSA. The findings reveal that our method adeptly captures temporal dependencies and dynamic shifts in time series as visual representations, offering novel insights for discerning fault patterns within such data. Notably, the maximum pressure variations at high-pressure and low-pressure points were 0.25 MPa and 0.07 MPa, respectively, with temperature shifts of 12 °C and 3.5 °C at the high and low-temperature points. The high-pressure and high-temperature points are particularly sensitive to changes in refrigerant charging, and parameters from these sections were utilized to construct the dataset. The CNN-MSA algorithm demonstrates consistent performance across various fault types, effectively delineating fault characteristics. The accuracies achieved by SVM, RF, CNN-AT, and MTF-CNN-MSA were 84.38 %, 73.75 %, 88.13 %, and 93.75 %, respectively. In comparison, the CNN-MSA algorithm was able to more accurately detect refrigerant charge faults at different levels.

制冷剂充注差异是空调系统的主要故障。达到最佳充注量对系统性能至关重要，这就凸显了精确制冷剂充注量预测的重要性。本研究介绍了一种通过整合马尔可夫变换场（MTF）、卷积神经网络（CNN）和多头自注意（MSA）机制来定量检测制冷剂充注误差的算法。利用高精度焓差室建立了可变制冷剂流量（VRF）制冷剂充注试验台。这种设置有助于分析系统参数对充注故障的敏感性，并帮助创建算法的训练数据集。与支持向量机 (SVM)、随机森林 (RF)、带自注意 (AT) 的 CNN 和 MTF-CNN-MSA 进行了比较分析。研究结果表明，我们的方法能够以可视化的方式捕捉时间序列中的时间依赖性和动态变化，为辨别此类数据中的故障模式提供了新的见解。值得注意的是，高压点和低压点的最大压力变化分别为 0.25 兆帕和 0.07 兆帕，高温点和低温点的温度变化分别为 12 摄氏度和 3.5 摄氏度。高压点和高温点对制冷剂充注量的变化特别敏感，因此利用这些部分的参数来构建数据集。CNN-MSA 算法在各种故障类型中表现出一致的性能，有效地划分了故障特征。SVM、RF、CNN-AT 和 MTF-CNN-MSA 算法的准确率分别为 84.38%、73.75%、88.13% 和 93.75%。相比之下，CNN-MSA 算法能更准确地检测出不同级别的制冷剂充注故障。

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引用次数: 0

Simulation and experimental study on splitting performance of Rectifier Nozzle Type Critical Distributor for multi-parallel evaporators 多平行蒸发器整流喷嘴型临界分配器分流性能的模拟和实验研究

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-22 DOI: 10.1016/j.ijrefrig.2024.10.022

Xiaofeng Li, Wenfu Zhang, Zhili Sun, Di Liang, Lei Yan, Haiwang Zhao, Jiale Chen, Fumin Hou, Xian Lv, Dandan Wang, Jiangman Yan

To solve the problem of performance degradation of multi-parallel evaporator due to inhomogeneous refrigerant distribution, a Rectifier Nozzle-Type Critical Distributor (RNCD) was developed. The multi-parallel evaporator test bench with RNCD and Centrifugal Distributor (CD) was built and the four parameters of cooling rate, outlet degree of overheat, pressure drop and cooling capacity of multi-parallel evaporator with RNCD were analyzed. Research shows that: The application of RNCD can improve the uniformity of superheat and cooling capacity while increasing the cooling rate of the system. When evaporator temperature is -28 °C, the ratio of overheat inhomogeneity of RNCD than CD was reduced by 0.58, and the ratio of cooling capacity inhomogeneity of branches was reduced by 0.45. The total pressure drop of the three components is roughly the same as that of the evaporator. RNCD can bear more pressure drop of the throttle valve. Combined with the simulation of experimental conditions, the study shows that RNCD has better distribution ability and can play the role of secondary throttle pressure drop. The RNCD proposes a novel approach to addressing the issue of inhomogeneous refrigerant distribution in refrigeration system as well as the optimization of the refrigeration system.

为解决制冷剂分布不均匀导致多并联蒸发器性能下降的问题，开发了整流喷嘴型临界分配器（RNCD）。建立了带有 RNCD 和离心式分配器（CD）的多并联蒸发器试验台，分析了带有 RNCD 的多并联蒸发器的冷却速率、出口过热程度、压降和冷却能力四个参数。研究表明RNCD 的应用可以改善过热度的均匀性和冷却能力，同时提高系统的冷却速率。当蒸发器温度为-28 ℃时，RNCD 的过热不均匀度比 CD 降低了 0.58，而分支的冷却能力不均匀度比 CD 降低了 0.45。三个组件的总压降与蒸发器的总压降基本相同。RNCD 可以承受更多的节流阀压降。结合实验条件的模拟，研究表明 RNCD 具有更好的分配能力，可以起到二次节流阀压降的作用。RNCD 为解决制冷系统中制冷剂分布不均匀的问题以及制冷系统的优化提出了一种新方法。

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引用次数: 0

Study on the friction characteristics of a self-lubricating linear compressor using vapor injection 利用喷气技术研究自润滑线性压缩机的摩擦特性

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-22 DOI: 10.1016/j.ijrefrig.2024.10.014

Shuo Zhang , Huiming Zou , Mingsheng Tang , Fanchen Kong , Wencong Shao , Zhouhang Hu

The self-lubricating linear compressor with aerostatic bearings has good prospect for the scenario which has difficulties of oil returning. This study presents a novel oil-free linear compressor and establishes a frictional damping model by using equivalent circuit approach to evaluate the mechanical performance of the compressor. The changes in friction damping characteristics of VISLLC under different piston strokes and injection pressure are analyzed. The flow resistance coefficients within the porous medium and gas gap are obtained by experimental tests and modeling analysis. Simulation results indicate that the equivalent frictional damping coefficient can be reduced by 36.1 % comparing with that of the non-injection and the efficiency can improved the by 17.2 %. The frictional damping coefficient in the porous bearing thickness of 0.9 mm at 600 kPa injection pressure is 3.64 N·s·m⁻¹.

采用空气静压轴承的自润滑线性压缩机在回油困难的情况下具有良好的应用前景。本研究提出了一种新型无油线性压缩机，并利用等效电路方法建立了摩擦阻尼模型，以评估压缩机的机械性能。分析了不同活塞冲程和喷油压力下 VISLLC 摩擦阻尼特性的变化。通过实验测试和建模分析获得了多孔介质和气体间隙内的流动阻力系数。模拟结果表明，等效摩擦阻尼系数比不喷射时降低了 36.1%，效率提高了 17.2%。在 600 kPa 注入压力下，厚度为 0.9 mm 的多孔轴承的摩擦阻尼系数为 3.64 N-s-m-1。

引用次数: 0

High-fidelity model development of CO2 booster refrigeration systems in supermarkets using field measurements 利用实地测量建立超市二氧化碳增压制冷系统的高保真模型

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-21 DOI: 10.1016/j.ijrefrig.2024.10.025

Wenzhuo Li, Ivan Korolija, Rui Tang, Dejan Mumovic

Supermarket refrigeration systems adopting traditional refrigerants with high global warming potential (GWP) have impacts on global warming for indirect and direct greenhouse gases (GHG) emissions. CO₂ is a popular low-GWP alternative. The transcritical operation of CO₂ systems worsens their energy performance, but provides recoverable heat as a heat source to reduce gas consumption. To evaluate operation performance, data-driven models, trained by historical data, are weak in implementation with datasets outside the scope of training data; in contrast, theoretical models have better extrapolation ability to calculate all operation conditions of CO₂ systems at supermarket. Existing theoretical modeling approaches often lack validation against the limited public-access data, which reduces model reliability for further applications, and adopt oversimplified inference methods for unmeasured variables, which increases the risks of breaking thermodynamic laws and lowering model accuracy. This study therefore develops a steady-state theoretical model for CO₂ booster refrigeration systems validated against field measurements from three UK supermarkets. The available measurements are utilized to the best level to ensure model accuracy and physical interpretability. Proposed methods to infer missing variables in CO₂ systems include condenser outlet temperature, evaporating temperature, compressor isentropic efficiency and compressor mass flow rate. Results show that proposed inference methods enhance the abilities of the proposed modeling approach to ensure data integrity, avoid breaking thermodynamic laws, and improve model accuracy by reflecting real-time actual values of unmeasured variables rather than rough assumptions. The proposed modeling approach provides satisfactory accuracy validated using high-resolution measurements across the whole year from three real supermarkets.

超市制冷系统采用全球升温潜能值（GWP）较高的传统制冷剂，间接和直接排放的温室气体（GHG）会对全球变暖产生影响。二氧化碳是一种流行的低全球升温潜能值替代品。二氧化碳系统的跨临界运行会降低其能效，但可提供可回收热量作为热源，从而减少气体消耗。为了评估运行性能，通过历史数据训练的数据驱动模型在使用训练数据范围之外的数据集时显得力不从心；相比之下，理论模型具有更好的外推能力，可以计算超市中二氧化碳系统的所有运行条件。现有的理论建模方法往往缺乏对有限的公开数据的验证，这降低了模型进一步应用的可靠性，并且对未测量变量采用了过于简化的推理方法，这增加了破坏热力学定律和降低模型精度的风险。因此，本研究为二氧化碳增压制冷系统开发了一个稳态理论模型，并根据英国三家超市的实地测量结果进行了验证。对现有测量数据进行了最佳利用，以确保模型的准确性和物理可解释性。提出的二氧化碳系统缺失变量推断方法包括冷凝器出口温度、蒸发温度、压缩机等熵效率和压缩机质量流量。结果表明，建议的推理方法提高了建议建模方法的能力，以确保数据完整性，避免破坏热力学定律，并通过反映未测量变量的实时实际值而不是粗略假设来提高模型精度。通过对三家真实超市全年的高分辨率测量结果进行验证，建议的建模方法具有令人满意的准确性。

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引用次数: 0

Characteristic analysis and diagnosis method optimization of scroll compressor pressure pulsation signal under voltage fluctuation 电压波动下涡旋式压缩机压力脉动信号的特性分析与诊断方法优化

IF 3.5 2区工程技术 Q1 ENGINEERING, MECHANICAL

International Journal of Refrigeration-revue Internationale Du Froid

Pub Date : 2024-10-21 DOI: 10.1016/j.ijrefrig.2024.10.024

Yanjie Zhao , Tonghe Zhang , Yongxing Song , Qiang Liu , Lin Liu , Ming Yu , Yi Ge

Under off-design conditions, scroll compressors can lead to reduced efficiency, motor damage, and even cause safety problems such as leaks or explosions. To solve the above problems, this paper analyzes the influence mechanism of different voltages on the spectrum of pressure pulsation signal and modulation signal and provides theoretical support for fault diagnosis and enhances the interpretability of the model. A voltage fault diagnosis method of scroll compressor based on Time-frequency Principal component Convolutional Network (TPCN) model is proposed. By demodulation analysis of the pressure pulsation signal of the low-pressure inlet and high-pressure outlet of the refrigerant in the scroll compressor, the spectrum information of the principal component modulation signal under different voltages is obtained. The pooling strategy is used to accurately identify and extract the fault information in the modulated signal spectrum as the input data of the model. The input data is divided into the training set and the test set according to the ratio of 8:2 to complete the training and testing of the fault diagnosis model. The experimental results show that the accuracy of TPCN model for the diagnosis of 5 types of faults reaches 100 %. The average accuracy of the model is 100 %, which indicates that the model has good stability.

在非设计工况下，涡旋式压缩机会导致效率降低、电机损坏，甚至引发泄漏或爆炸等安全问题。为解决上述问题，本文分析了不同电压对压力脉动信号和调制信号频谱的影响机理，为故障诊断提供了理论支持，并增强了模型的可解释性。提出了一种基于时频主成分卷积网络（TPCN）模型的涡旋压缩机电压故障诊断方法。通过对涡旋压缩机中制冷剂低压入口和高压出口的压力脉动信号进行解调分析，获得了不同电压下主分量调制信号的频谱信息。采用池化策略准确识别和提取调制信号频谱中的故障信息，作为模型的输入数据。输入数据按照 8:2 的比例分为训练集和测试集，完成故障诊断模型的训练和测试。实验结果表明，TPCN 模型对 5 种故障的诊断准确率达到 100%。模型的平均准确率为 100%，表明模型具有良好的稳定性。

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引用次数: 0