简谐脉动流过冷沸腾换热特性实验

摘要

To investigate the heat transfer characteristics of subcooled boiling in a pulsating flow, we observed the effect of amplitude and period pulsation on a vertical heating tube at different subcooled boiling stages.Our re-search results show that an increase in the pulsation amplitude or period intensifies heat transfer in the initial stage of subcooled boiling.In the final stage of subcooled boiling, the heat transfer deteriorates with increases in the pul-sation amplitude, such that the effect of the pulsation period on the heat transfer characteristics can be neglected. The pulsation amplitude influences subcooled boiling by changing the range of flow fluctuation and the pulsation pe-riod influences subcooled boiling by changing the degree of heat transfer between the fluid and the heated wall.%为研究简谐脉动对过冷沸腾换热的影响机理,本文以竖直加热圆管为研究对象,分析了入口过冷度不同工况下换热特性受脉动幅度和周期的影响.实验结果表明:在过冷沸腾初期,脉动振幅和脉动周期越大,换热效果越好;在过冷沸腾后期,脉动振幅越大,换热效果越差,而此时脉动周期对换热影响基本可以忽略,脉动振幅主要通过改变流量波动范围影响过冷沸腾换热程度,脉动周期主要通过改变流体与壁面间换热进行程度影响过冷沸腾换热程度.