Question about implementing "solve" in solvers
 

Dear Foamers,

I have been using OpenFOAM for more than a year, most of my case is about just use the exist solvers the software. Now, I want to get started about development my own solver.

It maybe a dull question to ask. But where can I find the code of "solve" function in the below sample code?

like
While(simple.loop())
{
Info<<"time= "<<runTime.timeName()<<nl<<endl;
while(simple.correctNonOrthogonal())
{
solve
(
fvm::ddt(T)
+fvm::div(phi,T)
-fvm::laplacian(DT,T)
);
}}

And how about laplacian, div?

Many thanks!

ddt, laplacian and so on are memebrs of fvm class