Time Accurate Computation of Unsteady Inlet Flows with a Dynamic Flow AdaptiveMesh

摘要

Research has been performed to obtain very accurate dynamic simulations ofsupersonic inlet unstart using CFD codes and a dynamic solution adaptive mesh algorithm developed at NCSU. The codes use Runge-Kutta time differencing and Advective Upwind Split Method spatial differencing in finite volume form. Other changes have been incorporated to improve the time accuracy when the computational mesh is dynamically adapted. Solutions have been obtained and animated for unstart of generic 2-D mixed compressions and fully supersonic inlets. Analysis of results revealed that laminar viscous flow unstart occurs by a separation/oblique shock mechanism rather than movement of a normal shock. Turbulent flow simulations reveal that initial shock motion occurs initially but then reverts to the separation/oblique shock mechanisms. 3-D steady and unsteady simulations are presented and conclusions drawn concerning the role of separation in inlet unstart. Computational fluid dynamics, Dynamic adaptive mesh, Mixed compression inlet unstart, Unsteady flow.