基于金属薄膜热源的喷雾冷却可视化实验研究

Visualization of Spray Cooling Based on Metal-Film-Heater

本文采用铝箔片作为模拟热源,结合红外热成像技术,对喷雾冷却换热特性进行可视化研究。发现相对于普通实心喷嘴,所喷射液滴轨迹具有切向力的旋转轨迹的喷嘴所得到的换热能力更强,但是在热沉表面温度分布上,不能产生带有旋转切向力的液滴的喷嘴效果更好;随着薄膜热源的输入功率的升高,其喷雾冷却的换热系数随之减少。在质量流量及喷嘴压力较高条件下,这种趋势更为明显。

A visualization of spray cooling using alumnium foil as heat source is conducted with the aid of the infrared thermal imaging technology.Compared with common solid nozzle,the nozzle able to produce droplets on rotating orbit of shearing force is shown to have stronger heat transfer ability.However,in terms of the temperature distribution on the metal film heater surface,the nozzle unable to produce droplets having shearing rotating orbit is found to perform better.Meanwhile,as the input power of the heat source increases,the heat transfer coefficient of spray cooling decreases,which tends to be more significant under relatively high mass flow rate and nozzle pressure.