黏性效应对高超声速飞行器特性的影响分析

Analysis of Viscous Effects on Hypersonic Vehicle Model Characteristics

针对高超声速飞行器的黏性效应,采用参考温度法建立高超声速飞行器气动黏性模型,对比研究了黏性效应对气动特性的影响.考虑到气动热使飞行器壁面温度升高的情况,分析了黏性阻力及飞行器弹性形变随壁面温度变化的规律,并对比研究了黏性效应对飞行器控制量(舵偏角与燃料当量比)的影响.最后,在考虑发动机热堵塞现象下,研究了黏性效应对飞行器高度、速度边界值的影响.结果表明:黏性效应主要影响飞行器阻力;黏性阻力随马赫数增大而增大,随高度升高而减小;随壁面温度升高,黏性阻力升高,黏性推阻比降低,机体弹性形变更加严重;黏性效应使飞行器飞行高度、速度边界区间变窄.

With regard to the viscous effects of hypersonic vehicle,the reference temperature method was adopted to establish the aerodynamic viscous model,and the influence of viscous effects on the aerodynamic characteristics was comparatively investigated. Considering the wall temperature rising caused by aerodynamic heating,viscous drag and flexible deformation variation with the wall temperature were analyzed,and the influence of viscous effects on the controls（elevator angle and stoichiometrically normalized fuel equivalency ratio（FER）） was comparatively investigated. Finally,considering the thermal choking of the scramjet,the influence of viscous effects on boundary values of velocity and altitude of the hypersonic vehicle was investigated. The results show that viscous effects mainly affect drag. The drag generated by viscous effects increases with the increase of Mach number,while decreases with the increase of height. With the rise of temperature,the viscous drag increases,the viscous thrust-drag ratio decreases and the elastic deformation becomes more severe. The viscous effects narrow the flying boundary of velocity and attitude.