【摘要】 基于VOF方法建立了板式脉动热管内气液两相流动和相变传热的三维非稳态数学模型,并进行了数值求解.研究了该型热管内气液两相流流型演化和相变传热特性,比较了不同加热功率条件下热管内的流型和温度分布.研究结果表明:该板式脉动热管在运行过程中出现的主要流型有泡状流、柱塞流、环状流;当加热功率为100和120 W时,启动工况下热管内总气相含气率会出现飞升;稳定循环运行工况下热管各点温度随时间做有规律的周期性脉动,加热段脉动幅度最大,绝热段次之,冷却段最小,温度脉动频率随着功率的增大而升高.更多还原

【Abstract】 Based on the VOF(volume of fluid) method,a three-dimensional unsteady model of vapor-liquid two-phase flow and heat transfer in a flat-plate pulsating heat pipes(FP-PHP) is developed and numerically analyzed to study the flow pattern transition and heat transfer in the FP-PHP.The effects of the heat load on temperature oscillation and distribution,and the thermal performance of FP-PHP were all investigated and discussed.The results indicate that the main flow patterns,including bubbly flow,slug flow and semi-annular/annular flow,are observed in FP-PHP.During start-up,the total volume fraction in the FP-PHP drastically increases until to the condition of steady directional circulation under the heating power of 100 and 120 W,while a periodical oscillation of fluid temperature occurs.The oscillation amplitude at adiabatic section is larger than that at condenser section but less than that at evaporator section.In addition,with increasing heat load,the temperature oscillation frequency increases.更多还原