首页|稀薄气体效应对高超声速边界层稳定性的影响

稀薄气体效应对高超声速边界层稳定性的影响

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
临近空间高超声速飞行器在跨越大气层飞行时可能经历从连续到稀薄流域。本文基于Navier-Stokes(NS)方程和NS改进模型研究了稀薄气体效应对高超声速边界层稳定性的影响。首先在传统线性稳定性理论(linear stability theory，LST)中引入壁面滑移条件和非线性输运模型，发展了适用于稀薄剪切流的拓展稳定性分析方法。然后重点分析了马赫数10、飞行高度55 km的尖平板绕流，研究了稀薄气体效应(包括壁面滑移效应和剪切非平衡效应)对边界层稳定性的影响机理。结果表明，对于基本流，稀薄气体效应使得边界层变薄，边界层剖面的广义拐点向壁面靠近。对于稳定性，稀薄气体效应通过影响基本流使第二模态更稳定，而通过修正稳定性方程使第二模态更不稳定，综合效应使得第二模态更稳定。然而，对于第一模态，稀薄气体效应始终起不稳定效果。这些结果从宏观角度揭示了近连续流域高超声速平板边界层的稳定性特征。
Rarefaction effects on hypersonic boundary-layer stability
Near-space hypersonic vehicles could experience both continuous and rarefied flow regimes during the flight through atmosphere.The rarefaction effects on hypersonic boundary-layer stability are studied based on the Navier-Stokes(NS)equations and an im-proved NS model.The conventional linear stability theory(LST)is extended for rarefied shear flows by adopting slip boundary conditions and nonlinear transport relations.A flow at Mach 10 over a flat plate at an altitude of 55 km is the main case of analysis.The separate and combined effects of rarefaction(including surface slip and shear nonequilibrium)on stability by in-fluencing the base flow and stability equation are clarified.The results show that for the base flow,rarefaction effects cause the boundary layer to become thinner and the generalized inflection point to move towards the wall.For stability,rarefaction effects have a stabilizing effect on the second-mode instability by influencing the base flow while a destabilizing effect by modifying the stability equation.The combined effects of rarefaction suppress the second-mode instability for different Mach number cases.However,for the first-mode instability,rarefaction effects play a destabilizing role.These results shed light on the hypersonic boundary-layer stability in the near-continuum regime from a macroscopic view.

Linear instabilityFlat-plate boundary layerRarefied nonequilibriumHypersonicSlip effects

欧吉辉、王晨悦、陈杰

展开 >

Laboratory of High-speed Aerodynamics,Tianjin University,Tianjin 300072,China

Department of Mechanics,Tianjin University,Tianjin 300072,China

Tianjin Key Laboratory of Modern Engineering Mechanics,Tianjin 300072,China

Linear instability Flat-plate boundary layer Rarefied nonequilibrium Hypersonic Slip effects

National Natural Science Foundation of ChinaNational Natural Science Foundation of China

1220230792152103

2024

10.1007/s10409-023-23184-x

力学学报(英文版)

力学学报(英文版)

CSTPCD
影响因子：0.363
ISSN：0567-7718
年,卷(期)：2024.40(3)