为了解决空间红外相机的高分辨率、高成品率及可维修性等问题,提出了先将6个线列探测器子模块拼接在一个“Z”字型的子基板上,再将多个(N≥5)这样的“Z”字型子基板通过精密拼接的方法以形成空间超长线列红外焦平面探测器.基于由多个子基板拼接形成的超长冷平台与单点冷源耦合以实现热交换的特点,针对超长冷平台温度均匀性小于1K及其与单点冷源间温度梯度小于5K的要求,建立了冷量传输通道的热网络模型,分析了影响冷量传输效率的主要因素,提出了优化各部件及不同部件螺接的接触热阻的方法,设计了两个“树状”柔性冷链实现了冷量向多基板冷平台高效传输.通过对加载不同总焦耳热时超长冷平台的温度均匀性及其与单点冷源间的温度梯度等热特性进行仿真和实验验证,结果表明超长冷平台温度均匀性误差小于0.05 K,温度梯度误差小于0.55 K,验证了由多个子基板拼接而成的超长冷平台与单点冷源间冷量传输模型合理可行,对于后续多基板精密拼接的工程应用提供重要参考.

界面热阻在热管理方面具有重要的研究价值与意义,对产品的可靠性,性能,功耗以及寿命等具有重要影响.介绍了界面热阻的测量方法,包括稳态方法,结构函数法,3ω法,激光光热法,激光闪光法,时域热反射法和频域热反射法等.稳态方法原理简单,测量时间长,准确度高,可用于测量块状材料的界面热阻.结构函数法,3ω法,激光光热法,激光闪光法,时域热反射法和频域热反射法属于瞬态方法,瞬态方法原理复杂,测量时间短,形式多样,可用于测量块状材料和微纳尺度材料的界面热阻.总结分析了材料的机械和热物理特性、材料表面形貌、界面压力、界面温度、界面之间的介质以及界面处化学成键状况等对界面热阻的影响.

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%.

The cold shield is an important part of the infrared detector assembly,and it will be cooled with the detector.Aiming at F2 cold shield for the 320 ×256,30 μm scale infrared detector,through cooling experiment with different technical conditions of cold shield in the same cold platform,the influence of the corresponding technical conditions of cold shield on the cooling process was studied,and the corresponding results were obtained under different technical conditions of cold shield.The results provide a reference for optimizing the thermal design of cold shield.

A design scheme of flexible cold strap according to the requirement of long linear IRFPA packaging was presented in this paper, the characteristics of long linear IRFPA and linear pulse tube cooler were summarized, design ideas and design methods based on the mechanical and thermal requirements of cold strap were proposed. For typical butting substrate size and working temperature, used partial flexible cold strap scheme was used, which was optimized by FEM tool, design requirements was achieved. Test dewar was made according to the design result, temperature difference of cold strap, flatness and temperature uniformity of butting substrate were verified. The test dewar has passed vibration testing. The test results show that the design scheme is correct and feasible.