CFD code structure (F90)

ma

I've read and written several CFD codes in Fortran, and come to know that the code structure is quite important as the code goes large. The commercial CFD codes may have a good structure but we have no chance to read them.

I am wondering how you guys construct your CFD code, particularly, TVD code for compressible reacting flow?

As for my self, several years ago, I put every thing in a single file and have a lot of "/common/...".

Later, I use a separte file, usually named PubVar.mod, to define public variables, and USE this module in the main code, which is a new attribute of Fortran 90.

Later, I found it is good to add another modue, usually named "GovEqu.mod" to encapsulate those related with governing equations, e.g., it may include subroutines like Get_Q(Q,p,T,u), Put_Q(Q,p,t,u), Get_E(Q,E), etc. The code sounds like having a "modular" structure.

Now I am going to add chemical reaction to such an existing code and have 3 options: (1) add to the main code (2) add to the GovEqu.mod (3) establish a new Chemistry.Mod

So what are your preference? Any discussion about how to improve a CFD code structure is welcome.

- ma