[mohsen.hashemzadeh]

Dear Foamers,

I am developing a new solver for fire modelling based on FireFOAM. I need to have two different regions (meshes). In the larger one (called environment) I have to solve a set of governing equations (PDEs).

For the other region (solid region), which should be embedded inside the environment region, I have to solve a set of ODEs. I know how to define two meshes and they work. The governing equations of each region are also working.

The only thing is that I want to access the field values (say velocity, temperature, ...) of the environment region inside the solid region to somehow couple the fields of each region.

I have two meshes, the definition of the meshes are based on the below link which I found useful:

Data exchange for internal field values between two different mesh

As FireFoam is a complex solver and there are numerous variables, it is not easy to define two fields (for each region) for all of the variables. Instead, I am looking for a way that I could access the data of the other field.

To explain a bit more, I have two meshes (mesh and emMesh, same as the link above). On the mesh, the gas phase equations are solved, while on the emMesh, I have a couple of fields that should be solved. I tried to access the mesh while solving the solid region equation (i.e. emMesh using

const fvMesh & mesh = objectRegistry::lookupObject<fvMesh>("mesh");

which couldn't be complied:

cannot call member function ‘const Type& Foam::objectRegistry::lookupObject(const Foam::word&) const [with Type = Foam::fvMesh]’ without object

or

const fvMesh & mesh = db().parent().lookupObject<fvMesh>("mesh");

which gives the below error:

error: ‘db’ was not declared in this scope;

Please kindly help.

[olesen]

It helps if you think of the mesh regions layout like a tree:

Time
|
|-- region1
|-- region2
|-- ...




\-- regionN

From your current mesh region, you first need to access its time() parent after which you can do a lookup for any of its siblings.