微型红外探测器组件快速冷却过程数值模拟分析

Numerical simulation on the fast cooling-down process of a miniature infrared detector module

随着探测技术的飞速发展,红外探测器获得了越来越广泛的应用。对一种快速启动的微型红外探测器内部结构进行了数值模拟和传热计算。模拟结果表明：接触热阻对探测器组件冷却过程和时间的影响显著,通过调整接触热阻的大小,探测器芯片冷却到90 K所用的时间在4~10 s之间变动。初始环境温度和光阑表面发射率对芯片的冷却效果影响不大。节流冷头温度的变化对探测器组件冷却影响较大,当节流冷头温度下降较慢时,其对芯片启动时间影响较大。在实验过程中可以通过优化接触热阻和节流冷头这两个因素来提高探测器组件冷却效果,从而达到更高的要求。

With the rapid development of detection technologies, the infrared detectors have gained more and more applications. The internal structure of a miniature infrared detector for fast cooling-down process was numerically simulated and analyzed in this paper. The simulating result shows that the thermal contact resistance has significant effect on the detector module cooling-down process. By adjusting the contact resistance, the cooling-down time of the detector chip from ambient temperature to 90 K are 4-10 s. The effects of the initial ambient temperature and the diaphragm surface emissivity show few influence on the cooling-down process of the chip. While the temperature of the throttling cool head has a great impact on the cooling-down process. The faster the temperature drops, the shorter the startup time of the chip. Therefore, the detector can be improved by optimizing the thermal contact resistance and the throttling cool head, to achieve the higher requirements.