Evaluating the Temporal Accuracy of Inlet Normal Shock Propagation Simulations

摘要

TTMOSPHERIC disturbances encountered by a high-speed civil transport (HSCT) may induce an inlet unstart (expulsion of the normal shock) depending on the magnitude of the disturbance and the unstart tolerance of the inlet/engine combination. The NPARC1 flow simulation software is being used to evaluate the unstart properties of a variety of inlet concepts, to support wind-tunne! tests aimed at evaluating inlet stability, and to support design of the inlet control system, Development of appropriate boundary conditions for unsteady Euler/Navier-Stokes inlet flow simulations has been under way for some time.2'3 Now that appropriate boundary conditions are available for these simulations, the numerical time accuracy of the code for these tasks has become an important issue.