Axisymmetric supersonic flow and Maxwell slip model

Update: December 17, 2018
OpenFOAM 4.x

Case directory

$FOAM_TUTORIALS/compressible/rhoCentralFoam/biconic25-55Run35

Summary

We calculate the supersonic air flow hitting the wall at an angle for 0.001 seconds.

The air flows in from the region "freestream" at 2713 m/s and out from the region "outlet". The region "cone" is a wall. Only side A in the figure below has no thickness, and the entire analysis region is wedge-shaped.

Model geometry Model geometry

For the wall of the region "cone", we use a Maxwell slip model that can represent multiple slip states depending on the temperature and curvature of the surface.

The turbulence model is not used, and the calculation is performed as a pseudo 2-dimensional mesh with one mesh in the circumferential direction of the wedge. And a converged solution is used as the initial condition.

The meshes are as follows, and the number of mesh is 32385.

Mesh Meshes
領域 outlet と領域 cone の結合部付近のメッシュ Mesh near the junction of region "outlet" and region "cone"

The calculation result is as follows.

Flow velocity at final time (U) Flow velocity at final time (U)
Pressure at final time (p) Pressure at final time (p)

We can see that the slip state changes discontinuously on a region "cone".

Commands

cp -r $FOAM_TUTORIALS/compressible/rhoCentralFoam/biconic25-55Run35 biconic25-55Run35
cd biconic25-55Run35

blockMesh
datToFoam grid256.dat

# Degenerate short edges and join them with edges in a line
CONST="constant"
cat $CONST/pointsHeader $CONST/points.tmp > $CONST/polyMesh/points
collapseEdges -overwrite

# Changed the patch type for boundary conditions to wedge
mv $CONST/polyMesh/boundary $CONST/polyMesh/boundary.bak
sed -f $CONST/wedgeScr $CONST/polyMesh/boundary.bak > $CONST/polyMesh/boundary
rm $CONST/polyMesh/boundary.bak

rhoCentralFoam

paraFoam

Calculation time

25分09.86 seconds *Single, Inter(R) Core(TM) i7-8700 CPU @ 3.20GHz 3.19GHz

Reference