Simulation of axisymmetric scramjet inlet flow fields using anti-diffusive WENO Navier-Stokes solver

摘要

This study is based on the theory of gas dynamics and uses the Navier-Stokes equations as the governing equations to solve the hypersonic flow problems of the scramjet. For the turbulent flow, we use the Spalart-Allmaras one equation turbulence model, which produces better results for near wall and boundary layer flow field problems. The lower-upper symmetric Gauss-Seidel implicit scheme, which enables results to converge efficiently under steady state conditions, is combined with the anti-diffusive weighted essentially non-oscillatory (WENO) scheme to yield an accurate and efficient simulation tool for an axisymmetric scramjet flow field analysis. Using the WENO scheme's high-order accuracy and its non-oscillatory solution at discontinuous regions, we can solve the hypersonic flow problems involving complex shock-shock/shock-boundary layer interactions inside the flow path. This simulation procedure is first verified against two existing partial examples to ensure its accuracy, and is then applied to a complete scramjet model with different initial conditions for a full flow field analysis. The aerodynamic data of Mach number, density, static temperature and pressure are obtained and the results discussed. The anti-diffusive WENO scheme produces more accurate resolution of shock and slip lines and their complex multiple interactions than other numerical approaches. This is of crucial importance for the scramjet complete flow field analysis as multiple shock-boundary layer and discontinuities interactions often occur within the long flow path.