{"title":"垂直管中超临界氮气传热恶化的实验和数值研究","authors":"","doi":"10.1016/j.supflu.2024.106376","DOIUrl":null,"url":null,"abstract":"<div><p>Supercritical cryogenic fluids exhibit significant potential for diverse applications across various industries, including liquid air energy storage, high-temperature superconducting cables, and hypersonic vehicle engine cooling. Heat transfer deterioration (HTD) poses a substantial risk to the system safety. In this study, we constructed an experimental system and performed numerical simulations to illustrate buoyancy (<strong>Bu</strong>) and thermal acceleration (<strong>Ac</strong>) effects on HTD of supercritical nitrogen (SCN<sub>2</sub>). The newly established thresholds for buoyancy and thermal acceleration (<strong>Bu</strong><sub>th</sub>=1.8×10<sup>−4</sup> and <strong>Ac</strong><sub>th</sub>=4.4×10<sup>−5</sup>), considering pseudo two-phase characteristics, can effectively capture buoyancy and thermal acceleration in the first and second HTD regions. The first region is influenced by the combined effect of buoyancy and thermal acceleration, while the second region is mainly influenced by thermal acceleration. The new correlations and thresholds accurately predict the occurrence of HTD and the peak position. The experimental and simulation results contribute to understanding the impact of buoyancy and thermal acceleration on SCN<sub>2</sub> HTD.</p></div>","PeriodicalId":17078,"journal":{"name":"Journal of Supercritical Fluids","volume":null,"pages":null},"PeriodicalIF":3.4000,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Experimental and numerical study on the heat transfer deterioration of supercritical nitrogen in a vertical tube\",\"authors\":\"\",\"doi\":\"10.1016/j.supflu.2024.106376\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Supercritical cryogenic fluids exhibit significant potential for diverse applications across various industries, including liquid air energy storage, high-temperature superconducting cables, and hypersonic vehicle engine cooling. Heat transfer deterioration (HTD) poses a substantial risk to the system safety. In this study, we constructed an experimental system and performed numerical simulations to illustrate buoyancy (<strong>Bu</strong>) and thermal acceleration (<strong>Ac</strong>) effects on HTD of supercritical nitrogen (SCN<sub>2</sub>). The newly established thresholds for buoyancy and thermal acceleration (<strong>Bu</strong><sub>th</sub>=1.8×10<sup>−4</sup> and <strong>Ac</strong><sub>th</sub>=4.4×10<sup>−5</sup>), considering pseudo two-phase characteristics, can effectively capture buoyancy and thermal acceleration in the first and second HTD regions. The first region is influenced by the combined effect of buoyancy and thermal acceleration, while the second region is mainly influenced by thermal acceleration. The new correlations and thresholds accurately predict the occurrence of HTD and the peak position. The experimental and simulation results contribute to understanding the impact of buoyancy and thermal acceleration on SCN<sub>2</sub> HTD.</p></div>\",\"PeriodicalId\":17078,\"journal\":{\"name\":\"Journal of Supercritical Fluids\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.4000,\"publicationDate\":\"2024-08-17\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Supercritical Fluids\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0896844624002110\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Supercritical Fluids","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0896844624002110","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Experimental and numerical study on the heat transfer deterioration of supercritical nitrogen in a vertical tube
Supercritical cryogenic fluids exhibit significant potential for diverse applications across various industries, including liquid air energy storage, high-temperature superconducting cables, and hypersonic vehicle engine cooling. Heat transfer deterioration (HTD) poses a substantial risk to the system safety. In this study, we constructed an experimental system and performed numerical simulations to illustrate buoyancy (Bu) and thermal acceleration (Ac) effects on HTD of supercritical nitrogen (SCN2). The newly established thresholds for buoyancy and thermal acceleration (Buth=1.8×10−4 and Acth=4.4×10−5), considering pseudo two-phase characteristics, can effectively capture buoyancy and thermal acceleration in the first and second HTD regions. The first region is influenced by the combined effect of buoyancy and thermal acceleration, while the second region is mainly influenced by thermal acceleration. The new correlations and thresholds accurately predict the occurrence of HTD and the peak position. The experimental and simulation results contribute to understanding the impact of buoyancy and thermal acceleration on SCN2 HTD.
期刊介绍:
The Journal of Supercritical Fluids is an international journal devoted to the fundamental and applied aspects of supercritical fluids and processes. Its aim is to provide a focused platform for academic and industrial researchers to report their findings and to have ready access to the advances in this rapidly growing field. Its coverage is multidisciplinary and includes both basic and applied topics.
Thermodynamics and phase equilibria, reaction kinetics and rate processes, thermal and transport properties, and all topics related to processing such as separations (extraction, fractionation, purification, chromatography) nucleation and impregnation are within the scope. Accounts of specific engineering applications such as those encountered in food, fuel, natural products, minerals, pharmaceuticals and polymer industries are included. Topics related to high pressure equipment design, analytical techniques, sensors, and process control methodologies are also within the scope of the journal.