[PratikChakraborty]

Hi all,

I wanted to understand what the situation is with regards to gravity for the pimpleFoam solver.

There doesn't seem to be a file for gravity, g in the constant folder. I am guessing that this means gravity is not considered (?).

However, the waveSubSurface tutorial under pimpleFoam/RAS/ does have a g file.

What does that mean? Is it that - in case there does exist that file, gravity will be considered?

[chenghui62000]

The g file also shows in tutorials\incompressible\pimpleFoam\RAS\rotatingFa nInRoom, However, I think the pimplefoam solver does not read the g file at all!

[okrochak]

Originally Posted by PratikChakraborty

Hi all,

I wanted to understand what the situation is with regards to gravity for the pimpleFoam solver.

There doesn't seem to be a file for gravity, g in the constant folder. I am guessing that this means gravity is not considered (?).

However, the waveSubSurface tutorial under pimpleFoam/RAS/ does have a g file.

What does that mean? Is it that - in case there does exist that file, gravity will be considered?

Originally Posted by chenghui62000

The g file also shows in tutorials\incompressible\pimpleFoam\RAS\rotatingFa nInRoom, However, I think the pimplefoam solver does not read the g file at all!

You are correct, pimpleFoam does not consider gravity force. You can look in the source code

https://www.openfoam.com/documentation/guides/latest/api/pimpleFoam_8C_source.html

:

\ddt{\vec{U}} + \div \left( \vec{U} \vec{U} \right) - \div \gvec{R} = - \grad p + \vec{S}_U

It may be possible to include gravity by using a source term with fvOptions file, but you're probably better off using a solver for heat-transfer, such as buoyantPimpleFoam or buoyantBoussinesqPimpleFoam.

You can read more here:

https://www.openfoam.com/documentation/guides/latest/doc/guide-applications-solvers-variable-transform-p-rgh.html

Regards, Alex