Hi:
I am a new user of OpenFoam,I have some questions about OpenFoam:
1)when I run sonicFoam/forwardstep case,I change the initial internal U field from (0,0,0) to (3,0,0),why the calculation became divergence?
2)I want a calculation with sonicTurbFoam to keep the CoNum constant instand of DeltaT constant ,how can I do this?

Hi,

I did 2) in the following way:
added the following line to the code after calculating CoNumber (# include CourantNo.H)

alfat = CFL/CoNum;
runTime.setDeltaT(alfat*runTime.deltaT().value());

Obviously, alfat had been previously defined as scalar and CFL was read from a file (defined as float).

Cheers,
Luiz

Sampaio
Thanks for your help.It works fine.

You should be aware that OpenFOAM already has a mechanism for maintaining a steady maximum CFL number.

See the dambreak tutorial and interFoam solver for details.

Eugene