星载红外探测器对高超声速飞行器探测距离的计算

为了有效地对临近空间高超声速飞行器进行探测预警，计算了星载空间红外探测器的作用距离。全面考虑到目标、背景到探测器之间的大气透过率差异、路径辐射以及点目标成像的弥散效应的影响，推导出新的作用距离模型，同时指出模型中的参数仅是波长的函数，与探测距离无关。基于空气动力学、发动机加力燃烧原理、羽焰温度流场简化模型，计算X-51A蒙皮、喷管及尾焰的红外辐射强度；综合自然环境的影响，建立海面背景的红外辐射模型。仿真指出，在动力段，X-51A的中波红外辐射强度和作用距离均高于长波波段，并且随着飞行速度的增加，中波和长波的辐射强度与作用距离都增大，考虑了成像弥散效应的作用距离明显小于无弥散效应的作用距离。表明使用中波对X-51A的探测能力优于长波，实际探测时弥散效应必须考虑。

Detection distance computation of the space borne infrared detector for hypersonic flight vehicles

The operation range of spaceborne infrared detector was computed for effective detection and early warning of hypersonic flight vehicles. Considering the influence of the different transmittance of target-detector and background-detector, path thermal and dispersion, a new operation range model was given. Parameters in the new model were the function of the wavelength and had no concern with the range. The infrared radiation characteristics computation model of X-51A's skin, nozzle and plume were given on basis of aerodynamics, engine's after burning theory, plume flow field and its simplified model. The infrared radiation model in the sea background was established on the influence of the environment. It's shown from simulations that the radiation intensity and operation range in the medium wave are larger than those in the long wave and they become larger with higher velocity. And the operation range becomes smaller when considering dispersion. It's inferred that the detecting ability is better in the medium wave and the dispersion should be considered in real detection.