Computation of Internal and External Compressible Flows Using EDICT

Abstract

Results are presented for finite element computations involving high speed, viscous compressible internal and external flows. The stabilized finite-element formulations for the Navier-Stokes equations in the conservation law form are solved using the conservation variables. To improve the accuracy of the base method, especially in the regions of flow that are associated with shocks, boundary-layers and their interactions, the Enhanced-Discretization Interface-Capturing Technique (EDICT) is utilized. An error indicator is employed to identify the regions in the computational domain that need enhanced discretization for increased accuracy. The method is implemented on a shared-memory parallel computer and is used to study complex flows, that involve shock-wave/boundary-layer interactions, in supersonic diffusers and wind-tunnels. The start-up problem in supersonic wind-tunnels, caused by a narrow second throat in the diffuser section, is simulated. This computation brings out some of the very interesting features of the unsteady dynamics of the start-up shock.