[gcengineer]

Sometimes the dimension of pressure is specified differently in 0/p file for different problems:

tutorials/basic/potentialFoam/cylinder
dimensions [0 2 -2 0 0 0 0];

tutorials/compressible/rhoSimpleFoam/angledDuctExplicitFixedCoeff
dimensions [1 -1 -2 0 0 0 0];

What tips me off to the correct dimension to use for a particular problem?

Is there a general rule for the correct dimension of pressure in 0/p file? Is it simply a matter of whether the problem is 2D or 3D? Compressible or incompressible?

I see that (M/LT2)/(M/L3) = L2/T2.

Thanks.

[nimasam]

one is pressure and the other one is pressure divide on density

[gcengineer]

Thank you, nimasam, for responding.

As I wrote, "I see that (M/LT2)/(M/L3) = L2/T2."

What I want to know is why does one case require M/LT2, but another requires L2/T2?

Is it 2D v 3D? Compressible v incompressible? Choice of solver?

[nimasam]

you should check each solver , but its pressure on density in some incompressible solvers

[gcengineer]

It appears that the dimension of pressure is M/LT2 for compressible solvers and L2/T2 for incompressible solvers. Here, Boussinesq solvers are incompressible (e.g., buoyantBoussinesqSimpleFoam, buoyantBoussinesqPimpleFoam).

If there is an exception to this rule, I would appreciate knowing about it.

Thanks.

[nimasam]

forexample interFoam which is two-phase incompressible solver

[gcengineer]

Yes. However, for the cases in /tutorials/multiphase/interFoam, there is no 0/p, but 0/p_rgh has dimension M/LT2.

Thanks again.