构形树状小通道内的流动沸腾换热特性

FLOW BOILING CHARACTERISTICS IN CONSTRUCTAL TREE-SHAPED MINICHANNEL

本文建立了构形树状小通道内流动沸腾换热模型,数值研究了树状通道网络内的流动沸腾换热特性,并与具有相同换热面积、入口直径的蛇形通道就泵功消耗、流动沸腾压降、通道温度变化和热有效性等指标进行了性能对比分析。研究表明,与蛇形通道相比,构形通道具有流动沸腾压降、泵功消耗小的优势,且其温度均匀性、热有效性也均优于蛇形通道。当热流密度为20 W/cm^2时,构形树状通道内流体的泵功消耗约为蛇形通道的一半,其热有效性为蛇形通道的1.9倍。

The flow boiling characteristics in constrnctal tree-shaped minichannel nets are numerically investigated using a one-dimensional model. The pump power requirement, pressure drop, tempera- ture dli%rence and thermal efficiency of the constructal tree-shaped minichannel are evaluated and compared with those of the corresponding traditional serpentine channel. The results indicated that the flow boiling in constructal tree-shaped minichannnel possesses less pressure drop, lower pumping power requirement, better temperature uniformity and higher thermal efficiency. The pumping power requirement in the constructal tree-shaped minichannel is about half of the corresponding serpentine channel＇s, and the thermal efficiency is 1.9 times of that in serpentine channel with wall heat flux of 20 W/cm2.