Mach 3 inviscid compressible supersonic flow of a perfect gas over a forward-facing step.
Physics and modelling
The test case models the steady-state shock structure in a supersonic flow over a forward-facing step. The gas behaviour is modelled using
the perfect gas behaviour with constant material properties.
The solution algorithm used here is based on the bounded solution of the pressure equation and can cover speeds ranging from incompressible to highly supersonic.
The segregated algorithm is formulated in terms of a density predictor, momentum predictor and a pressure solution, with an explicit update of pressure and
density. This is used in conjunction with an automatic error-driven local mesh refinement and coarsening algorithm, designed to capture the position of the
shocks. The refinement algorithm uses embedded hexahedral and degenerate hexahedral cells and controls the mesh grading using the “1-irregularity” principle.
OpenFOAM solver
sonicFoam, adapted to include the error estimation and local refinement tools from the errorEstimation and shapeMeshTools libraries.
Author
Simulation by Nabla Ltd.
Images and animations
Figure 13:
Adaptive mesh, refinement only.
Figure 14:
Adaptive mesh, refinement with coarsening.
Figure 15:
Mach number field.
Figure 16:
Adaptive refinement: a detail of the refined mesh.
