飞机蒙皮红外辐射的瞬态温度场分析

飞机蒙皮温度场是形成飞机红外图像的基本因素,掌握其瞬态分布特性与控制机制对于飞机相关的红外技术有重要帮助.通过分析控制蒙皮温度场的传热过程,建立了包括飞机内部换热、蒙皮外气动对流与辐射换热的瞬态耦合传热数理模型.引入壁面热流函数,将蒙皮外部热环境与飞机内部换热进行解耦计算,采用热网络法与蒙特卡罗法进行飞机内部传热分析,利用FLUENT软件进行蒙皮外气动对流换热模拟,建立了飞机蒙皮瞬态温度场的数值方法.通过模拟计算,获得了不同飞行状况下飞机蒙皮的瞬态温度场,分析了相关因素的影响.

ANALYSIS ON THE TRANSIENT TEMPERATURE-FIELDS FOR INFRARED RADIATION OF AIRCRAFT SKIN

The aircraft skin temperature is a basic factor determining the infrared image of aircraft,so the knowledge on the transient temperature is important.By analyzing the heat transfer mechanism governing the skin temperature,the physical and mathematical models for the transient coupled heat transfer were put forward,in which the effects of internal heat transfer in an aircraft cabin and the aerodynamic convection and radiative heat transfer outside the skin were included.A wall heat flux function was introduced to separate the numerical prediction of internal heat transfer in aircraft from that of thermal effects outside the skin.The thermal network method combined with the Monte Carlo method was used to analyze the internal heat transfer and the FLUENT code was employed to simulate the aerodynamic convection outside skin.By numerical simulation,the transient temperature fields of an aircraft skin under various flight statuses were obtained and discussed.