【摘要】 针对重力热管两相流数值模拟中传统Lee相变模型因采用固定传质时间弛豫系数(β)导致的仿真精度不足、难以收敛至稳态等问题，提出了一种具有冷凝因子自调节功能的改进Lee模型。该模型通过UDF嵌入Fluent实现，经172.87 W和376.14 W加热工况验证，结果表明：改进模型显著提升了温度预测精度，各段平均误差降至3.3%以下，同时将工质质量损失率从传统模型的80.7%降至0.528%,并真实地反映管内两相工质分布与流动特性，为提升重力热管CFD仿真的准确性与稳定性提供了有效方法。更多还原

【Abstract】 This study addresses the issues of insufficient simulation accuracy and difficulty in converging to a steady state in the numerical simulation of two-phase flow within gravity heat pipes, which arise from the traditional Lee phase-change model’s use of a fixed mass transfer relaxation coefficient(β).To overcome these limitations, an improved Lee model with self-adjusting condensation factors is proposed.The model is implemented in Fluent via a user-defined function(UDF)and validated under heating conditions of 172.87 W and 376.14 W.The results demonstrate that the improved model significantly enhances temperature prediction accuracy, reducing the average error in each section to below 3.3%,while decreasing the working fluid mass loss rate from 80.7% in the traditional model to 0.528%.Furthermore, it accurately captures the distribution and flow characteristics of the two-phase working fluid inside the pipe.This study provides an effective method for improving the accuracy and stability of CFD simulation for gravity heat pipes.更多还原