Cryogenics最新文献

{"title":"Evaluation of localized mechanical properties of modified N50 welded joints at cryogenic temperature through a digital image correlation technique","authors":"Jingjing Dai ,&nbsp;Liancheng Xie ,&nbsp;Weijun Wang ,&nbsp;Jijun Xin ,&nbsp;Bixi Li ,&nbsp;Rong Bao ,&nbsp;Yining Huang ,&nbsp;Chuanjun Huang ,&nbsp;Wentao Sun ,&nbsp;Wei Wang ,&nbsp;Li Shi ,&nbsp;Xinran Shan ,&nbsp;Laifeng Li","doi":"10.1016/j.cryogenics.2024.103960","DOIUrl":"10.1016/j.cryogenics.2024.103960","url":null,"abstract":"<div><div>The modified N50 austenitic stainless steel has been determined to be applied as the superconducting magnet supporting material of the Chinese Fusion Engineering Test Reactor (CFETR), especially the jacket material of the CICCs of both the TF coils and the CS coils and the case material of the TF coils, which inevitably requires welding connection. The welding process generally results in welding defects as well as degradation of cryogenic mechanical properties of metallurgical inhomogeneous zones. However, limited research has been reported to demonstrate the distinct localized performance of these zones at cryogenic temperature. The present paper presents an approach to characterize localized mechanical properties of the modified N50 welds at both room temperature (300 K) and cryogenic temperature (6 K). We identified the welding zone (WZ) through metallographic analysis and then the boundaries of the heat-affected zone (HAZ) were recognized by hardness measurements at room temperature. Finally, the localized optical digital image correlation (DIC) technique was used to obtain the localized yield strength <em>R</em>_p0.2 and percentage extension <em>e</em> of the WZ, the HAZ, and the base metal (BM) at both room and cryogenic temperature, of which the observed trend is verified through comparison with that of hardness measurements at room temperature. The technique proposed provides the localized measurement of cryogenic tensile properties of weld metals and also presents experimental data on different zones of the modified N50 welded joints as a jacket material for the next-generation fusion reactors.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103960"},"PeriodicalIF":1.8,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel approach to thermal insulation modelling in soft and medium vacuum insulation systems","authors":"Gideon Volschenk ,&nbsp;Michael O'Shea ,&nbsp;Bryan Shaughnessy","doi":"10.1016/j.cryogenics.2024.103946","DOIUrl":"10.1016/j.cryogenics.2024.103946","url":null,"abstract":"<div><div>The accuracy of vacuum-dependent models for predicting thermal performance of Multi-Layer Insulation (MLI) and other layered insulation systems is critical for the development of novel solutions in the aerospace and energy sectors, particularly long distance superconductors and cryogenic transfer lines. This paper presents a review of the current state of the art in cryogenic vacuum insulation systems and their associated modelling techniques and test methods. Current modelling techniques, namely the Lockheed and McIntosh MLI models, are compared to cryogenic, boil-off calorimeter test data for 3 types of MLI from the current literature. Both current models provide acceptable accuracy at high vacuum pressures but deviate from the test data when gas conduction becomes the dominant heat transfer mechanism (<span><math><mi>K</mi><mi>n</mi><mo>≤</mo><mn>1</mn></math></span>). Neither of the current models follow the characteristic S-curve observed by researchers during insulation tests. This paper presents the introduction of a novel modelling approach for layered insulation systems though changes to the current state of the art, specifically at soft (<span><math><msub><mrow><mi>p</mi></mrow><mrow><mi>v</mi><mi>a</mi><mi>c</mi></mrow></msub><mo>≤</mo><mn>7.5</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>5</mn></mrow></msup><mtext> mTorr</mtext></math></span>) and medium vacuum (<span><math><msub><mrow><mi>p</mi></mrow><mrow><mi>v</mi><mi>a</mi><mi>c</mi></mrow></msub><mo>≤</mo><mn>7.5</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>2</mn></mrow></msup><mtext> mTorr</mtext></math></span>) pressures, by substituting the gas conduction term in both equations with alternative terms based on the system Knudsen number (<em>Kn</em>) and molecule mean free path (<em>l</em>). This results in a stronger pressure dependence across the vacuum regime. Both modified models exhibited the characteristic S-curve with significantly reduced errors over the entire range.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"144 ","pages":"Article 103946"},"PeriodicalIF":1.8,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Progress in measuring techniques and thermal radiative properties of metals at cryogenic temperatures: A review","authors":"Abdul Rehman Hashmi ,&nbsp;Bo Wang ,&nbsp;Fatima Saadat ,&nbsp;Zhihua Gan","doi":"10.1016/j.cryogenics.2024.103950","DOIUrl":"10.1016/j.cryogenics.2024.103950","url":null,"abstract":"<div><div>In recent years, the development in measurement techniques of thermal radiative properties has attracted much attention to cryogenic applications, including space exploration, cryogenic research, medical applications, instrument design, planetary exploration and remote sensing, cryogenic storage and transportation. This paper discusses the importance of emissivity / absorptivity measurement, the factors they depend on, and the respective measurement methods, including calorimetric and radiometric. This paper also summarizes the published data on emissivity and absorptivity related to aluminum and stainless steel. It highlights the importance of surface treatment of materials, providing valuable insight into the significance of emissivity in cryogenic applications, which can serve as a reference for future research in this field.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103950"},"PeriodicalIF":1.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of temperature and heat input on helium isotope separation driven by an entropy filter","authors":"Liguo Wang ,&nbsp;Qianxi Qu ,&nbsp;Wanyin Zhao ,&nbsp;Huan Chen ,&nbsp;Niannian Dai ,&nbsp;Peng Jia ,&nbsp;Dong Xu ,&nbsp;Laifeng Li","doi":"10.1016/j.cryogenics.2024.103952","DOIUrl":"10.1016/j.cryogenics.2024.103952","url":null,"abstract":"<div><div>To understand the effect of temperature and heat input on helium isotope separation driven by an entropy filter, the thermomechanical flow of superfluid helium through an entropy filter for obtaining high purity ⁴He is experimentally investigated. For this method, there are two important indicators: separation flow (flow rate) and separation effect (³He concentration). The separation flow rate is examined at various temperatures ranging from 1.6 K to 1.9 K of feed helium. Different heat inputs (Q) are applied to the entropy filter outlet to drive superfluid ⁴He flowing through the porous element. The results demonstrate that the flow rate increases as the feed helium temperature decreases and heat input increases. Simultaneously, ³He diffusion is detected as the superfluid helium passes through the entropy filter. The concentration of ³He, filtered at different temperature ranging from 1.6 K to 1.9 K, are analyzed using HELIX SFT Static Vacuum Mass Spectrometer. The findings reveal that the ³He concentration decreases with an increase in the temperature of the feed helium bath. ³He concentration of feed helium is around <span><math><mrow><mn>3.3</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>-</mo><mn>8</mn></mrow></msup></mrow></math></span>. Specifically, the ³He concentration in the filtered helium at 1.6 K is approximately <span><math><mrow><mn>3.2</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>-</mo><mn>10</mn></mrow></msup></mrow></math></span>, while at 1.9 K, it reduced to <span><math><mrow><mn>2.2</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>-</mo><mn>10</mn></mrow></msup></mrow></math></span>. This suggests that ³He diffusion in He II is inversely proportional to the He II temperature from 1.6 K to 1.9 K, resulting in a lower ³He concentration at higher temperatures.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103952"},"PeriodicalIF":1.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cryogenic thermosiphon used for indirect cooling of superconducting magnets","authors":"Weronika Głuchowska ,&nbsp;Tomasz Banaszkiewicz ,&nbsp;Matthias Mentink ,&nbsp;Benoit Cure ,&nbsp;Alexey Dudarev ,&nbsp;Shuvay Singh","doi":"10.1016/j.cryogenics.2024.103951","DOIUrl":"10.1016/j.cryogenics.2024.103951","url":null,"abstract":"<div><div>A thermosiphon is a thermodynamic phenomenon that facilitates the circulation of cryogen within a cooling system, relying solely on gravitational forces and phase change. This mechanism leverages the variations in the density of the cryogenic fluid throughout the entire cooling loop, creating a pressure gradient. This gradient serves as the primary driving force for the circulation of the cryogen. To negate the necessity of a circulation pump, it is crucial to determine the geometry of the cooling loop, the configuration of the thermosiphon, its height, and the vertical placement of the cryogen phase separator. This paper introduces a simplified computational model and the geometric calculations of the cryogenic thermosiphon for two distinct configurations of the indirect cooling loop for superconducting magnets.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103951"},"PeriodicalIF":1.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0011227524001711/pdfft?md5=1815c15c0724607e310fc5f4e9825e85&pid=1-s2.0-S0011227524001711-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Delamination analysis of the epoxy impregnated REBCO racetrack coil under thermal stress based on a 3D model","authors":"Yansong Shen ,&nbsp;Zhidong Chen ,&nbsp;Yunpeng Wei ,&nbsp;Yongdou Liu","doi":"10.1016/j.cryogenics.2024.103947","DOIUrl":"10.1016/j.cryogenics.2024.103947","url":null,"abstract":"<div><div>Superconducting coils made of Rare-Earth-Barium-Copper-Oxide (REBCO) coated conductor (CC) exhibit superior electromagnetic performance. Employing epoxy impregnation can improve the structural integrity of the superconducting coils. However, the delamination behavior is observed in the epoxy impregnated REBCO coil when the environment temperature cool from the room temperature to 77 K. In previous studies, there is a few researches on the delamination and mechanical behavior of the epoxy impregnated racetrack coil. Therefore, this study proposes a three-dimensional (3D) mechanical-thermal model which incorporates the cohesive zone material (CZM) to investigate the delamination mechanisms in epoxy impregnated REBCO racetrack coils during cooling. We found that the coil experienced a higher tensile radial stress at the semicircular part than the straight part during the cooling process. This leads to that the delamination area tends to appear initially in the semicircular part with large tensile radial stress. And the stress concentration generated at the edge of the delamination area in the semicircular part can cause the extension of the edge of the delamination area to the straight part. In addition, the influences of the thermal expansion coefficient (CTE) of the mandrel and overband on the coil delamination behavior are studied in this paper. It is found that the radial stress, the initial position of the delamination, and the degree of delamination are affected by the CTE of the mandrel and overband. And the delamination of the coil can be avoided by reducing the tensile radial stress of the coil through reducing the CTE of the mandrel or increasing the CTE of the overband. And the prevention of the delamination in the semicircular part can obviously avoid the occurrence of the delamination in the straight part of the racetrack coil.</div></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103947"},"PeriodicalIF":1.8,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142311106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing dynamic stability of HTS maglev systems with preloading method","authors":"Ye Hong,&nbsp;Zhichuan Huang,&nbsp;Zihan Wang,&nbsp;Jiwang Zhang,&nbsp;Jun Zheng","doi":"10.1016/j.cryogenics.2024.103945","DOIUrl":"10.1016/j.cryogenics.2024.103945","url":null,"abstract":"<div><p>High temperature superconducting (HTS) bulks have strong flux pinning capabilities and are widely used in various fields. Their self-stabilizing characteristics also provide new ideas for ultra-high-speed rail transit. For HTS maglev systems, operational stability, curve negotiation and safety when subjected to external forces are very important. Due to the hysteresis effect of superconducting bulks, they do not always return to their initial positions after deviating from the levitated position in an alternative external magnetic field. In some cases, the levitation system can be destroyed. Studies have shown that preloading can enhance quasi-static levitation performance. Therefore, this paper conducts a detailed analysis of the quasi-static levitation and guidance forces of HTS bulks above a Halbach permanent magnet guideway (PMG) under conditions with and without preloading. Additionally, the dynamic responses of the HTS bulks under lateral or vertical pulsed excitations are studied, with a particular focus on the final equilibrium position offset after disturbance. The results indicate that preloading can suppress the attenuation of the levitation force, enhance the guidance performance, and raise stiffness in both lateral and vertical directions. It also effectively suppresses position deviation from disturbance and increases the maximum excitation force threshold for system instability. This study provides practical insights for HTS maglev applications.</p></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103945"},"PeriodicalIF":1.8,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142228964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diffusive solubility of nitrogen in Propane: Measurement from 96 K to 227 K at 0.1 MPa","authors":"Yihong Li ,&nbsp;Zhaozhao Gao ,&nbsp;Junxian Li ,&nbsp;Zhikang Wang ,&nbsp;Xiaoyu Fan ,&nbsp;Wei Ji ,&nbsp;Liubiao Chen ,&nbsp;Junjie Wang","doi":"10.1016/j.cryogenics.2024.103944","DOIUrl":"10.1016/j.cryogenics.2024.103944","url":null,"abstract":"<div><p>The burgeoning demand for large-scale energy storage has catalyzed the advancement of Liquid Air Energy Storage (LAES) technology. However, the liquid-phase propane cold storage process in LAES systems encounters a significant challenge: the dissolution of nitrogen protection gas in propane poses a substantial risk to both operational safety and performance. Given the dearth of data on the diffusive solubility of nitrogen in propane under constant atmospheric pressure and low-temperature conditions, this study constructed a testbench and conducted experiments within a temperature range of 96–227 K at a pressure of 0.1 MPa. The molar diffusive solubilities at 227 K, 176 K, 139 K, and 96 K are 0.030 %, 0.177 %, 0.297 %, and 0.962 %, respectively. Besides, this study also fits a calculation equation for the diffusive solubility of nitrogen in propane, which applies to the propane cold storage process in LAES systems.</p></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103944"},"PeriodicalIF":1.8,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142164737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical analysis on dynamic evolution characteristics of cryogenic cavitation through a Venturi tube","authors":"Guang Zhang ,&nbsp;Kai Wang ,&nbsp;Miao Yu ,&nbsp;Abhilash Suryan ,&nbsp;Zu Chao Zhu ,&nbsp;Zhe Lin","doi":"10.1016/j.cryogenics.2024.103937","DOIUrl":"10.1016/j.cryogenics.2024.103937","url":null,"abstract":"<div><p>Venturi tube can be used to measure the flow rate of stable single-phase fluid, which plays an important role in chemical industry, energy, aerospace and other fields. Due to the complex physical properties of cryogenic fluids, it is of great significance to study the cavitation characteristics of cryogenic fluids for practical engineering. In this paper, the modified Zwart cavitation model is used to study the evolution characteristics of cryogenic cavitation in Venturi tube and its relationship with turbulent kinetic energy under different pressure ratios by using dimensionless number <em>P</em>_r instead of cavitation number. The <em>P</em>_r value affects the development of cavitation to a large extent. When <em>P</em>_r = 1.3, cavitation is in a stable development mode. When <em>P</em>_r = 2.3, the development mode of cavitation changes from steady state to dynamic state. The temporal and spatial correlation between cavitation and vortex structure is studied by <em>Q</em>-criterion, and the geometric similarity between cavitation cloud and vortex structure in the development process is analyzed. The entropy production caused by velocity gradient change, turbulent dissipation and wall shear stress is further analyzed by entropy diagnosis method. The results show that the change of <em>P</em>_r value plays a leading role in the distribution of entropy production, and the generation and collapse of cavitation in the evolution process also have a great influence on the distribution of entropy production.</p></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103937"},"PeriodicalIF":1.8,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142158035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-coated thick superconducting films for metal–organic deposition using trifluoroacetates","authors":"Takeshi Araki ,&nbsp;Mariko Hayashi ,&nbsp;Nao Kobayashi","doi":"10.1016/j.cryogenics.2024.103939","DOIUrl":"10.1016/j.cryogenics.2024.103939","url":null,"abstract":"<div><p>Metal-organic deposition using trifluoroacetates (TFA-MOD) is known to yield uniform superconducting wires by a liquid growth mode. However, it has been difficult to prepare thick films because of drying stress during the calcining process. To avoid the drying stress, conventional crack-preventing chemicals such as H(CH₂)₈COOH are applied in conventional metal–organic deposition. However, large amounts of hydrogen atoms react with fluorine atoms during calcining process in TFA-MOD, and the consequent increased harmful carbon residue decreases superconductivity of the resulting films. To avoid the chemical reaction, new crack-preventing chemicals such as H(CF₂)₈COOH were applied to prepare single-coated thick films. A low ratio of hydrogen atoms decreases the chemical reaction and generates hydrogen fluorine gas, consequently suppressing the carbon residue. Above the calcining temperature, the crack-preventing chemical is decomposed into low-boiling-point chemicals such as CF₂CF₂ or CF₃CF₃. Consequently, single-coated thick film having low carbon residue and sufficient superconducting current per width was realized. For a long time, the authors have studied other possible candidate crack-preventing chemicals. Newly introduced fluorine ion measurement of decomposed materials during the calcining process revealed the nature of the crack-preventing chemicals. Based on the accumulated results, we have concluded that among over one million chemicals there are only two groups suitable for preparing single-coated thick superconducting films by TFA-MOD. One group is hydrogenated perfluoro-carboxylic acids such as H(CF₂)₈COOH and the other group is perfluoro di-carboxylic acids. With H(CF₂)₈COOH, using a single-coating process we were able to achieve a 560 nm-thick YBa₂Cu₃O_6.93 film having <em>J</em>_c of 4.70 MA/cm² (77 K,0T). Compared with a standard 150 nm-thick YBa₂Cu₃O_6.93 film having <em>J</em>_c of 7.70 MA/cm² (77 K,0T), the critical current per width is improved to about 227 %.</p></div>","PeriodicalId":10812,"journal":{"name":"Cryogenics","volume":"143 ","pages":"Article 103939"},"PeriodicalIF":1.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142149300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}