高速飞行器紫外辐射特性研究进展

Research progress on ultraviolet radiation characteristics of hypersonic vehicles

为了进一步明晰高速飞行器紫外辐射的相关机理与计算方法、辐射特性和未来研究方向,基于高速非平衡流场理论和紫外辐射跃迁机理,详细分析了光谱吸收系数、分子数密度等参数的计算过程,以及逐线计算法和辐射传输方程的应用场景。目前主要是通过模拟和实验手段对NO和OH分子的碰撞–辐射模型进行研究,以预测紫外光谱和辐射特性。此外,本文还综述了紫外辐射传输建模现状,明确了高速飞行器不同位置、观测角度以及飞行高度和速度对紫外辐射亮度的影响,并指出不同比例的紫外辐射源也会对飞行器尾焰的紫外辐射特性产生影响。通过对近几十年的地面和飞行实验进行研究,分析实验数据与模拟结果的差异,提出模型中可能存在的问题和不足。未来工作将集中于构建一体化辐射模型、发展先进紫外测试技术并拓展非平衡诊断技术,以满足目标特性探测和热防护系统优化等实际需求。

This study first delves into computational methods,radiation characteristics,and underlying mechanisms of ultraviolet radiation emitted by hypersonic vehicles,the study of which holds immense significance for ensuring safe flight.Based on the principles of hypersonic non-equilibrium flows and the transition mechanisms of ultraviolet radiation,a comprehensive analysis is provided on the computational procedures for determining parameters like the spectral absorption coefficient and molecular number density.Furthermore,the study explores the application scenarios of the line-by-line calculation method and the radiative transfer equation.Numerical and experimental investigations using collision-radiation models on the ultraviolet spectral and radiation characteristics of NO and OH molecules are summarized.The current status of ultraviolet radiation transmission modeling is also presented,focusing on the influence of geometry configuration,observation angle,flight altitude,and flight speed on the ultraviolet radiation.The deficiencies of these models are identified by comparing simulation results with those obtained by recent ground and flight experiments.Future research should prioritize the development of an integrated radiation model and advanced ultraviolet testing and non-equilibrium diagnostic techniques to meet practical needs such as target characteristic detection and thermal protection system optimization.