Abstract This paper focuses on the transient process of the pipe cooling by the internal flow of cryogenic fluid, which is a so-called cryogenic line chill-down process. Due to the increasing use of cryogenic fluid in various industries, the heat transfer characteristics during the line chill-down process are followed with great interest. One of the biggest concern is that there are no universal heat transfer correlations for simulating the chill-down process. This research aims to extend the quenching database with liquid oxygen and predict the cryogenic line chill-down process with a one-dimensional homogeneous model. The line chill-down experiments are performed by liquid oxygen with the mass flux range from 15.9 kg/m2-s to 75.9 kg/m2-s. A 7 m long stainless steel 316 horizontal tube is used as the test section. The empirical correlations for heat transfer coefficient of single-phase vapor convection and film boiling are suggested based on the chill-down experimental data of liquid oxygen, liquid argon, and liquid nitrogen. The line chill-down process is simulated by applying the empirical correlations in a one-dimensional homogeneous model. The feasibility of the dynamic simulation model is verified in the mass flux up to 868 kg/m2-s by simulating the chill-down experimental data in the literature. Moreover, the characteristics of the critical heat flux, critical heat flux temperature, and minimum heat flux temperature are also investigated by comparing various experimental data and the empirical correlations. This study provides not only the open experimental data with liquid oxygen, which is rarely found in the literature but also the numerical simulation method, which predicts the line chill-down time within ± 10% error.

中文翻译：

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各种低温流体在线冷却过程中的传热研究

摘要 本文重点研究了低温流体内部流动对管道冷却的瞬态过程，即所谓的低温管线冷却过程。由于在各个行业中越来越多地使用低温流体，因此人们对管线冷却过程中的传热特性非常感兴趣。最大的担忧之一是没有用于模拟冷却过程的通用传热相关性。本研究旨在扩展液氧淬火数据库，并用一维均质模型预测低温管线冷却过程。线冷却实验由液氧进行，质量通量范围为 15.9 kg/m2-s 至 75.9 kg/m2-s。7 m 长的不锈钢 316 水平管用作测试部分。基于液氧、液氩和液氮的冷却实验数据，提出了单相蒸汽对流和薄膜沸腾传热系数的经验关系式。通过在一维均匀模型中应用经验相关性来模拟生产线冷却过程。通过模拟文献中的冷却实验数据，在高达 868 kg/m2-s 的质量通量中验证了动态模拟模型的可行性。此外，通过比较各种实验数据和经验相关性，还研究了临界热通量、临界热通量温度和最小热通量温度的特性。这项研究不仅提供了液氧的开放实验数据，