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

Design passive magnetic mechanisms with modular magnet configuration for axial gas force balance in miniature scroll compressors 利用模块化磁铁配置设计无源磁力机构，以平衡微型涡旋式压缩机中的轴向气体力

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-07 DOI: 10.1016/j.ijrefrig.2024.06.007

{"title":"Design passive magnetic mechanisms with modular magnet configuration for axial gas force balance in miniature scroll compressors","authors":"","doi":"10.1016/j.ijrefrig.2024.06.007","DOIUrl":"10.1016/j.ijrefrig.2024.06.007","url":null,"abstract":"<div><p>Miniature scroll compressors (MSCs) are recognized for their superior characteristics—compact design, silent operation and energy-saving performance. One of its main challenges is to maintain dynamic sealing between the fixed and orbiting scrolls during the operation. This paper adopts a passive magnet mechanism (PMM) to balance the axial gas force in MSCs. The PMM with an integral magnet configuration (IMC) is investigated first, and the dimensions of the magnet and fixed ring are found as the paramount factors to determine the magnitude of axial magnetic force. However, the IMC is unable to follow the unsteady characteristics of the target axial gas force, so the scrolls will experience a large period of over-sealing during its operation.</p><p>To overcome this limitation, an innovative modular magnet configuration (MMC) is proposed and investigated. The height of each magnet segment is treated as individual design variable, and genetic algorithm optimization is carried out to seek for the best force balance performance according to two indices—maximum force difference (MFD) and integral-average force difference (IAFD). With precise design of each magnet segment, the MMC is able to provide unsteady magnetic force and thus better balance performance. Compared with the IMC, the improvements are up to 52 % reduction of MFD and 66 % reduction of IAFD. The derived superior MMC designs reveal a common characteristic that the “N” and “E” magnets have short segments at their outer fringe and the “S” and “W” magnets have short segments at their inner fringe. The axial magnetic force characteristics of the IMC and MMC are validated by prototype experiments.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141409196","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

Numerical investigate on the heat transfer performance and mechanical analysis of a water sublimator 水升华器传热性能的数值研究与力学分析{zh} 水升华器传热性能的数值研究与力学分析

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-04 DOI: 10.1016/j.ijrefrig.2024.06.008

Desheng Ma , Liping Pang , Jie Zhang

{"title":"Numerical investigate on the heat transfer performance and mechanical analysis of a water sublimator","authors":"Desheng Ma , Liping Pang , Jie Zhang","doi":"10.1016/j.ijrefrig.2024.06.008","DOIUrl":"10.1016/j.ijrefrig.2024.06.008","url":null,"abstract":"<div><p>Water sublimators play a critical role in efficiently managing the high thermal load of spacecraft in a vacuum environment, ensuring their proper functioning. This article focuses on a novel cold plate water sublimator driven by a porous sublimation tube structure, which is still in the theoretical research stage. Numerical methods are employed to study the evaporation, freezing, and sublimation processes, with validation against experimental data. The average absolute error of the four operating conditions is 1.33 K, and the ice layer thickness error is 8.33 %. Additionally, a method to calculate the effective thermal conductivity of porous aluminum foam is proposed, with a model error of 9 %. The sublimator's heat transfer characteristics are significantly influenced by the porosity of the aluminum foam and sublimation tubes. The impacts on temperature behavior, ice thickness, feed water pressure, and stress are carefully examined. Results reveal aluminum foam porosity of 0.7 and sublimation tube porosity of 0.3. Moreover, the study explores how different heat loads affect the sublimator's operation mode. Heat loads above 2 W/cm<sup>2</sup> cause evaporation and dryness within the sublimation tube, while excessively small heat loads lead to ice formation and increased stress on the aluminum foam structure. These findings provide valuable insights for water sublimator design.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141394065","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

Insight into quality, microstructure, and protein physicochemical properties of Monopterus albus frozen with liquid nitrogen 洞察液氮冷冻白芒果的质量、微观结构和蛋白质理化特性

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-03 DOI: 10.1016/j.ijrefrig.2024.05.033

Haiqi Yang , Hongyan Lu , Xianglong He , Jiwang Chen , Lijuan Peng , E Liao

{"title":"Insight into quality, microstructure, and protein physicochemical properties of Monopterus albus frozen with liquid nitrogen","authors":"Haiqi Yang , Hongyan Lu , Xianglong He , Jiwang Chen , Lijuan Peng , E Liao","doi":"10.1016/j.ijrefrig.2024.05.033","DOIUrl":"10.1016/j.ijrefrig.2024.05.033","url":null,"abstract":"<div><p><em>Monopterus albus</em> is highly susceptible to spoilage due to high protein and moisture contents while frozen storage can effectively prolong the shelf-life. To study the effect of liquid nitrogen freezing (LNF) on quality, microstructure of ice crystal and muscle fiber, and physicochemical properties of proteins, <em>Monopterus albus</em> was frozen at -20 °C by refrigerator (RF, control), -50 °C, -80 °C, and -110 °C by LNF, respectively. The -110 °C LNF exhibited the highest freezing rate among four groups, contributing to the formation of small ice crystals with more uniform distribution and alleviating the damage to muscle fiber. In -110 °C LNF group, protein secondary structure changed relatively subtle, resulting in high protein solubility, Ca<sup>2+</sup>-ATPase activity, and total sulfhydryl content, as well as low surface hydrophobicity and disulfide bond content. LNF retarded the rise of TVB-N value, prevented the loss of immobilized and free water, and maintained water holding capacity and shear force. In conclusion, -110 °C LNF was recommended a promising freezing process for frozen <em>Monopterus albus</em> due to less alteration of quality and alleviation of protein denaturation.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141281532","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

Numerical study of a CO2 swirl ejector with lubricating oil 使用润滑油的二氧化碳漩涡喷射器的数值研究Etude numérique d'un éjecteur tourbillonnant de CO2 avec huile lubrifiante

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-03 DOI: 10.1016/j.ijrefrig.2024.06.002

Chengzhang Li , Fang Liu , Maogang He , Yue Liu

{"title":"Numerical study of a CO2 swirl ejector with lubricating oil","authors":"Chengzhang Li , Fang Liu , Maogang He , Yue Liu","doi":"10.1016/j.ijrefrig.2024.06.002","DOIUrl":"10.1016/j.ijrefrig.2024.06.002","url":null,"abstract":"<div><p>At present, most simulations of ejectors ignore the presence of lubricating oil, which may affect the accuracy of the results. Additionally, there has been less research conducted on the influence of motive nozzles with swirl generators on the performance of ejectors. In this study, a heterogeneous mixture model was developed for a three-phase swirl ejector equipped with a motive nozzle featuring a swirl generator. This article examines the performance of swirl ejectors under supercritical conditions using three-dimensional numerical simulations conducted in ANSYS. The study explores swirl ejectors with varying helical angles of 77°, 64°, 58°, 50°, 37° . The study also takes into account the influence of lubricating oil to enhance the practicality of the research. Firstly, lubricating oil with a volume fraction of 2 % was introduced into both the motive and suction streams, followed by conducting an ejection analysis. The results indicate that the swirl enhances the entrainment ratio, and the swirl strength can be modified by changing the helical angle. A smaller helical angle results in greater swirl strength and a higher entrainment ratio. When the helical angle is 37° and the helical pitch is 20 mm, a swirl number of 0.42, an entrainment ratio of 0.998, and an effective entrainment ratio of 0.863 is achieved. However, when the oil circulation ratio in the suction stream is increased from 2 % to 10 % while keeping the oil circulation ratio of the motive stream constant, the entrainment ratio decreases.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141279647","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

Quality and microstructure of tilapia fillets (Oreochromis niloticus) subjected to different freezing methods 不同冷冻方法下缇罗非鱼鱼片的质量和微观结构

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-03 DOI: 10.1016/j.ijrefrig.2024.06.004

Karen Lendengue de Matos Regalado , Kelly Lendengue de Matos Regalado , Francielly Corrêa Albergária , Ana Luiza de Souza Miranda , Maria Emília de Sousa Gomes , Jaime Vilela de Resende

{"title":"Quality and microstructure of tilapia fillets (Oreochromis niloticus) subjected to different freezing methods","authors":"Karen Lendengue de Matos Regalado , Kelly Lendengue de Matos Regalado , Francielly Corrêa Albergária , Ana Luiza de Souza Miranda , Maria Emília de Sousa Gomes , Jaime Vilela de Resende","doi":"10.1016/j.ijrefrig.2024.06.004","DOIUrl":"10.1016/j.ijrefrig.2024.06.004","url":null,"abstract":"<div><p>The Nile tilapia (Oreochromis niloticus) fillets were frozen with static air (SA) at -20 °C, air blast freezing (AF) at -25 °C, combined method (CM - immersion in liquid nitrogen followed by AF) and cryogenic freezing (CF - immersion in liquid nitrogen). The effects of different freezing methods and of storage time at -18 °C (0, 30, 60 and 90 days) on fillet quality were evaluated. The temperature records were obtained, and the freezing times were determined by monitoring the temperatures of the geometric centers of the fillets. For CF, CM, AF and SA, the freezing times were 5.32, 127, 146 and 268 min, respectively. The quality of the frozen fillets was evaluated by measuring pH, volatile nitrogenous bases (TBV-N), thiobarbituric acid reactive substances (TBARS), and fatty acids and by obtaining a texture profile and performing scanning electron microscopy (SEM). The samples frozen by CF, after storage, had the highest levels of TBV-N because the high freezing rate produced superficial cracks that negatively affected the quality of the fillets. Freezing the samples with SA produced the worst quality indices and the microstructure was visibly damaged, with greater spaces between the fibers left by ice crystals. For all parameters evaluated, freezing with AF and CM resulted in fast freezing rates and better-quality tilapia fillets for 90 days of storage.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141275141","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

A novel simulation method for CO2 ejector containing lubricant oil 含润滑油二氧化碳喷射器的新型模拟方法

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-03 DOI: 10.1016/j.ijrefrig.2024.06.009

Yue Liu , Fang Liu , Hailong Liu

引用次数: 0

Quantification of two-phase flow in a microchannel heat exchanger header based on capacitance measurement 基于电容测量的微通道热交换器集管中两相流的定量分析

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-03 DOI: 10.1016/j.ijrefrig.2024.06.003

Jiajia Song , Hequn Liu , Chao Yuan , Ran Wang , Jinqing Peng , Lizhi Wang , Haobo Jiang , Houpei Li

{"title":"Quantification of two-phase flow in a microchannel heat exchanger header based on capacitance measurement","authors":"Jiajia Song , Hequn Liu , Chao Yuan , Ran Wang , Jinqing Peng , Lizhi Wang , Haobo Jiang , Houpei Li","doi":"10.1016/j.ijrefrig.2024.06.003","DOIUrl":"10.1016/j.ijrefrig.2024.06.003","url":null,"abstract":"<div><p>The two-phase distribution has always been one of the research focuses of microchannel heat exchangers, because the maldistribution could seriously affect the heat transfer performance. This paper developed a capacitive method to quantify the two-phase distribution of vapor-liquid flow in the aluminum header of a microchannel heat exchanger. A flexible capacitance sensor was used to quantify the two-phase distribution with R134a. The inlet mass fluxes vary from 17.47 kg m<sup>−2</sup> s<sup>−1</sup> to 52.42 kg m<sup>−2</sup> s<sup>−1</sup> and inlet vapor qualities range from 0.2 to 0.6. The normalized time-averaged capacitance signal was processed by a Gaussian function to obtain the mathematical expectation and the standard deviation. The local vapor quality in the header was solved for using a correlation derived from the pre-experiments. The distribution of local vapor quality showed that gases were concentrated upstream of the header, while liquids were concentrated in the middle and lower reaches. The local vapor quality reached a minimum and remained constant at 0.1 in the middle and lower reaches, unaffected by changes in inlet conditions. As the mass flux increased, both the local vapor quality maximum point and the minimum point in the header were shifted back toward the downstream. Additionally, the increase of mass flux caused the fluctuation of the standard deviation increased, which meant the stability of the flow decreased. The two-phase flow measurement technique based on flexible capacitance sensors proposed in this study realized the extension of the capacitive method from the experimental stage to the industrial application stage.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141280769","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 improvement of a Stirling-type two-stage pulse tube cooler by using stepped displacer plus bypasses phase shifter 利用阶梯式位移器和旁路移相器提高斯特林型双级脉冲管冷却器的性能

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-06-03 DOI: 10.1016/j.ijrefrig.2024.06.001

{"title":"Performance improvement of a Stirling-type two-stage pulse tube cooler by using stepped displacer plus bypasses phase shifter","authors":"","doi":"10.1016/j.ijrefrig.2024.06.001","DOIUrl":"10.1016/j.ijrefrig.2024.06.001","url":null,"abstract":"<div><p>Stirling-type pulse tube cooler (SPTC) is the most prospective thermoacoustic refrigerator due to its long lifetime, high reliability and low vibration, and the phase shifter significantly affects the energy conversion efficiency of SPTC. A novel phase shifter of the stepped displacer plus bypasses (SD-B) is proposed in this paper. Thermoacoustic impedance characteristics of the stepped displacer (SD) and the stepped displacer plus bypasses (SD-B) are analyzed. Based on a two-stage SPTC, the effect of additional combined DC flows in the system is first investigated. Results indicate that the cooling capacity could be improved through introducing additional DC flows in the positive direction from the hot end of regenerator to pulse tube. While for SD, negative DC flows are induced due to the clearance seal gaps between the displacer piston and cylinder shell. Thus, SD-B is explored to improve energy conversion efficiency through naturally introducing DC flows by bypasses. The influence of the opening diameter of two bypasses is investigated, and comparisons between the SD and SD-B are performed. Results indicate that with SD-B, the cooling capacity at 20 K achieves a maximum of 2.04 W with a relative Carnot efficiency of 13.0 %, 56.9 % higher than that of SD.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141274747","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

Thermodynamics of freezing water inside a self-pressurizing elastic tank and its departure from isochoric condition 自加压弹性罐内水结冰的热力学及其偏离等温线条件的情况

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-05-31 DOI: 10.1016/j.ijrefrig.2024.05.032

Ricardo Romero-Méndez , Francisco G. Pérez-Gutiérrez , Mihir Sen

引用次数: 0

Energy and exergy analysis of an experimental NH3-LiNO3 air-conditioning absorption system 实验性 NH3-LiNO3 空调吸收系统的能量和放能分析

IF 3.5 2区工程技术

International Journal of Refrigeration-revue Internationale Du Froid Pub Date : 2024-05-27 DOI: 10.1016/j.ijrefrig.2024.05.031

D. Colorado , W. Rivera , R.A. Conde-Gutiérrez , J.C. Jiménez-García

{"title":"Energy and exergy analysis of an experimental NH3-LiNO3 air-conditioning absorption system","authors":"D. Colorado , W. Rivera , R.A. Conde-Gutiérrez , J.C. Jiménez-García","doi":"10.1016/j.ijrefrig.2024.05.031","DOIUrl":"https://doi.org/10.1016/j.ijrefrig.2024.05.031","url":null,"abstract":"<div><p>An energy and exergy analysis of an experimental air-conditioning absorption system operating with the ammonia-lithium nitrate mixture has been performed. The system was operated under controlled and steady-state conditions. The main operating parameters, such as flow ratio, coefficient of performance, exergy coefficient of performance, and exergy destruction in each one of the main components, were determined at different heat sources and condensing temperatures. The coefficients of performance varied between 0.5 and 0.65, while the exergy coefficients of performance varied between 0.1 and 0.2. Clear trends were found for the coefficient of performance and flow ratio as a function of the generator and condenser temperatures; however, no trends were found in the exergy coefficients of performance due to the high variability of the ambient temperature. The highest values of the exergy destruction occurred in the generator, followed by the condenser and the evaporator, while the lowest values were obtained in the absorber and the economizer.</p></div>","PeriodicalId":14274,"journal":{"name":"International Journal of Refrigeration-revue Internationale Du Froid","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141540676","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