Supersonic flow hitting a rectangular obstacle

Update: December 17, 2018
OpenFOAM 4.x

Case directory

$FOAM_TUTORIALS/compressible/rhoCentralFoam/forwardStep

Summary

A virtual non-viscous gas flow, "normalized" to have a sound velocity of 1 m/s at a temperature of 1 K, hitting an obstacle at supersonic speed is calculated for 4 seconds.

The gas flows in from the region "inlet" at 3 m/s (Mach number 3) and out from the region "outlet". The region "top" and "bottom" are symmetric boundaries, and the region "obstacle" is a slip wall.

Model geometry Model geometry

The turbulence model is not used, and the analysis is performed in 2-dimensions.

The physical properties of the gas are specified in the file constant/thermophysicalProperties as follows.

mixture
{
    specie
    {
        nMoles          1;
        molWeight       11640.3;
    }
    thermodynamics
    {
        Cp              2.5;
        Hf              0;
    }
    transport
    {
        mu              0;
        Pr              1;
    }
}

The meshes are as follows, and the number of mesh is 16128.

Mesh Meshes

The calculation result is as follows.

The flow velocity is as follows.

0.5 Flow velocity at 0.5 sec (U) Flow velocity at 0.5 sec (U)
Flow velocity at 2.5 sec (U) Flow velocity at 2.5 sec (U)
Flow velocity at 4 sec (U) Flow velocity at 4 sec (U)

And the pressure is as follows.

Pressure at 0.5 sec (p) Pressure at 0.5 sec (p)
Pressure at 2.5 sec (p) Pressure at 2.5 sec (p)
Pressure at 4 sec (p) Pressure at 4 sec (p)

Note that the upper region of the computational domain, "top", is a symmetric boundary.

Commands

cp -r $FOAM_TUTORIALS/compressible/rhoCentralFoam/forwardStep forwardStep
cd forwardStep

blockMesh
rhoCentralFoam

paraFoam

Calculation time

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