Understanding conjugate solver implementation in openfoam
 

Hello Everybody,

I am doing M.Tech. in Modeling and Simulation, University of Pune, India. My project title is "Development of Conjugate Gradient Solver in OpenFOAM". I am trying to understand the implementation of the linear solvers, specifically, PCG.C solver in openfoam.

I dont understand the "scalarField& psi" & "scalarField wA(nCells)" variables are what exactly.

It would be great if someone could help me!
Umesh