利用红外热图开展通用航空飞行器气动热特性试验

Experiment of the characteristic of aerodynamic heating on CAV using infrared thermograpy

为了对通用航空飞行器(CAV)从近连续流到稀薄过渡流气动热特性进行研究,用红外热图技术在地面试验中测量了在典型轨道参数状态下CAV表面的热流分布。首先介绍了气动热试验研究所用的高超声速低密度风洞、红外热像仪等主要仪器设备的性能参数以及高超声速通用航空飞行器模型。其次介绍了高超声速低密度风洞气动热试验采用的3种模拟准则即粘性干扰参数、总焓与壁面焓差参数和克努曾数。最后,在马赫数M∞=7、12,攻角α=0°、12°、24°试验条件下,获得了CAV模型迎风面、背风面、侧面典型的流场结构图、红外热图和热流分布,并对CAV模型在不同状态下迎风中心线与翼前缘热流的试验结果、迎风中心线试验结果与工程计算结果进行了比较。研究表明:翼边缘热流大小呈现"马鞍形"分布,攻角变化对气动加热影响比较明显。

To study the characteristic of aerodynamic heating on common aviation vehicle（CAV） from near continuous flow region to rare transitional flow one,the surface aerodynamic heat flux distribution on CAV was measured in the ground test with infrared thermographic technique under the typical orbital parameter conditions.The function and parameter of hypersonic low density wind tunnel and infrared camera as well as the shape characteristic of the CAV were given in this paper firstly.Three simulation means such as viscous interaction parameter,enthalpy difference between total enthalpy and wall enthalpy and Knudsen number parameter adopted in the hypersonic low density wind tunnel were presented.At the test conditions M ∞ =7,α =0°,12° and M ∞ =12,α =24°,heat transfer distributions on the whole model surface,typical flow field schlieren pictures and infrared mappings were obtained.The heat transfer results at the model windward centerline,windward wing forward edge and theoretical computation were compared at different Mach number and different attack angle.Test result shows that heat flux distributions on windward wing forward edge possesses of shape as saddle,that the influence of the variety of attack angle on aerodynamic heating is distinct.