基于VOF模型对两相闭式热虹吸管传热性能及机理的模拟研究

Simulation of Heat Transfer Performance and Mechanism of Two-Phase Closed Thermosyphon Based on VOF Model

建立数值模型对两相闭式热虹吸管进行模拟研究,验证并分析了模型的可行性.通过设定加热功率分别为207. 35 W、276. 46 W、345. 58 W、414. 69 W、483. 81 W、552. 92 W、622. 04 W,工质分别为纯水和乙醇,倾角分别为30°、45°、60°、75°、90°,利用可视化技术结合沸腾传热机理分析加热功率、工质种类、倾角对两相闭式热虹吸管传热性能的影响.结果表明:不发生传热恶化的情况下铜-纯水、铜-乙醇两相闭式热虹吸管总热阻均随加热功率增大而减小;研究范围内,铜-纯水两相闭式热虹吸管最佳加热功率在414. 49～552. 92 W之间;相同加热功率条件下,铜-乙醇两相闭式热虹吸管传热性能更佳,且有更大的临界热流密度;加热功率为207. 35 W时,铜-乙醇两相闭式热虹吸管最佳倾角在45°～75°之间.

A model has been developed allowing to simulate a two-phase closed thermosyphon.Its feasibility has been verified.The heating power has been set as207.35W,276.46W,345.58W,414.69W,483.81W,552.92W,622.04W,respectively.The working fluid is pure water and ethanol,and the inclination angle is30°,45°,60°,75°and90°,respectively.The influence of heating power,working fluid and inclination angle on the heat transfer performance of a two-phase closed thermosyphon was analyzed by using visualization technology combined with boiling heat transfer mechanism.The results indicated that in a certain range without heat transfer deterioration,the heat transfer performance of the two-phase closed thermosyphon with pure water and ethanol increased with the increase of heating power,and the optimal heating power of the two-phase closed thermosyphon with pure water was between483.81W and552.92W.Under the condition of the same heating power,the two-phase closed thermosyphon with ethanol has better heat transfer performance and larger critical heat flux.In addition,when the heating power was207.35W in this study,the optimal dip angle of the two-phase closed thermosyphon with ethanol as working fluid was between45°and75°.