超长线列红外探测器杜瓦组件辐射热评估方法研究

Research on Evaluation Method of Radiant Heat of Long Linear IRFPA Dewar

超长线列红外探测器杜瓦组件大多采用桥式结构力学支撑,利用多点柔性冷链实现冷平台温度均匀。杜瓦组件结构复杂,利用传统辐射热公式计算相对困难。本文针对两种结构的8000元超长线列杜瓦组件,先用ANSYS有限元模拟出两种杜瓦的温度场并提取出辐射热;然后设计实验测试杜瓦内12个典型位置温度,验证了温度场准确性。同时基于材料的热导率和温度梯度计算热流,从而间接计算出辐射热。研究结果表明,有限元仿真辐射热与实验计算辐射热误差在2%左右。

In most long linear infrared focal plane （IRFPA） Dewars, the detectors are supported by a bridge structure. Flexible thermal links are used to maintain uniform temperature of the cold platform. It is difficult to calculate the radiant heat of Dewar components using an empirical formula. In this study, the radiant heat of a Dewar is simulated using the ANSYS finite element method. Furthermore, the temperature field of the Dewar components is experimentally measured. The heat flow is calculated based on the thermal conductivity and temperature gradient. Consequently, the radiant heat is calculated indirectly. The results show that the deviation between the radiant heats simulated using ANSYS and calculated indirectly using the temperature field is approximately 2%.