坦克高温表面相变红外抑制装置传热分析

Heat transfer analyzing of phase change infrared restraining device on tank′s high temperature surface

为了降低坦克高温表面的红外辐射特性,设计了相变红外抑制装置,建立了传热模型,利用FLUENT软件进行了传热分析,并进行了实验验证,温度计算值与实验值对比,最大相对误差小于6.5%。传热分析结果显示,在坦克导热和太阳辐射等因素的作用下,相变材料发生恒温相变,液相率逐渐变大,红外抑制装置温度较坦克表面温度下降40%;坦克内热源温度的升高、相变材料厚度的减小均可导致相变提前开始、相变持续时间缩短;相变材料熔点温度的下降使相变开始时间提前,同时使红外抑制装置的温度降低。

In order to reduce infrared radiating character of tank′s high temperature surface,phase change infrared restraining device was designed.Then heat transfer model was established,which was analyzed by FLUENT software and testified by experiment.The maximum relative error between calculating temperature values and experimenting temperature values was under 6.5%.The results of heat transfer analysis show that material′s phase changes at fixed temperature and liquid fraction of phase change material（PCM） increases under the effect of tank′s conduction and sun radiation,and infrared restraining device′s temperature is reduced by 40% compared with tank surface′s;material′s phase change becomes earlier and phase change durative time becomes shorter when tank′s inner heat source temperature rises and PCM thickness decreases;decreasing of PCM melting temperature advances phase change starting time,meanwhile,reduces the temperature of infrared restraining device.