选取去离子水、甲醇、乙醇和丙酮为工质,考察不同工质不同充液率的振荡热管运行特征,寻找影响振荡热管传热性能的物性因素。结果表明:在小功率时,传热性能受是否启动振荡及振荡流速支配,与动力黏度密切相关;随加热功率增大,振荡流速加快,不同工质振荡热管温度振荡频率和幅度差别渐小,动力黏度和液态比热容、汽化潜热共同影响振荡热管传热性能;在大功率时,振荡流速较快,充注汽化潜热、比热容大的工质振荡热管传热性能更具优势。振荡热管和物性的关联分析可为认识不同情况下振荡热管的传热机理和工作特性、建立振荡热管理论模型提供参考。
Deionized water,methanol,ethanol and acetone were chosen as working fluids to investigate operation and heat transfer characteristics of pulsating heat pipes(PHP).The experiment was designed to find out critical physical properties for the heat transfer of PHP under different conditions.The results showed that at small heating power,heat transfer depended on the speed of oscillation,and the key factor was kinetic viscosity.As the heating power increased,oscillatory flow accelerated accordingly,and the differences in frequency and amplitude of temperature oscillation gradually decreased,indicating the heat transfer of PHP was affected by kinetic viscosity,liquid specific heat and latent heat.As the heating power increased to a certain point,oscillatory flows of different WFs became faster and,at this stage,WFs of high latent heat and specific heat were preferable for heat transfer.The correlation study on the physical properties of WFs and the heat transfer performance of PHP may help to understand the heat transfer mechanism and operation characteristics of PHP at different situations and provide reference for the establishment of theoretical model.