[hxaxtma]

Hi guys,
I am working the last days on the following problem:

During a compressible simulation (rhoPimpleFoam) I am introducing a heat source via fvOptions during runtime over a cellSet using perfectGas as equation of state.

As a testcase, my domain is surrounded by walls, so the density should be constant and result in a pressure rise.

The problem is that the density changes, also in my closed system. This does not make sense.

How can i overcome this issue? What is wrong with my setup?

fvOptions:

heatSource
{
    type            scalarSemiImplicitSource;
    active          on;
    timeStart       0.01;
    duration        1e-04;
	
    selectionMode   cellSet;
    cellSet      heatSourceCellSet;
    volumeMode      absolute;
    injectionRateSuSp
        {
            e          (17000000000 0);
        }
}

p-BC:

internalField uniform 101325;

boundaryField
{
    
   "(.*_wall)"
    {
        type zeroGradient;
    }
   "(.*_empty)"
    {
        type empty;
    }      
    
}

T-BC:

internalField uniform 298;

boundaryField
{
    
   "(.*_wall)"
    {
        type zeroGradient;
    }
   "(.*_empty)"
    {
        type empty;
    }      
    
}

U-BC

   "(.*_wall)"
    {
        type fixedValue;
        value	uniform (0 0 0);
    }

   "(.*_empty)"
    {
        type empty;
    }

I did already changed the pressure and Temperature BCs to fixedValue, nothing changed...

So what ist the problem here?

In the attachement you can see p,T and rho at t=0.01s, when the source term is activated. The density is decreasing over the cellSet area.

[hxaxtma]

No one has an idea?

[random_ran]

How about using incompressible solver?

[hxaxtma]

Since there are compressible effects present, incompressible treatment is not suitable...

[hxaxtma]

Still need help on this...