CFD Online Discussion Forums - OpenFoam 9: Cannot use postProcess to calculate MachNo

Hi all.

I am following WolfDynamics course to solve flow past a cylinder, using a compressible solver: rhoPimpleFoam case 24.

The instructions are as follow: https://imgur.com/a/e65aP0i
Everything except step 8 works. Step 8 involves;

Code:

rhoPimpleFoam -postProcess -func MachNo

The error tells me to use foamRun, so I did:

Code:

foamRun -postProcess -func MachNo

and got the same error. Te error I got (for both case) is: https://imgur.com/a/YrAkz2V

So I tried:

Code:

postProcess -func "MachNo(U)"

and got error such as "functionObjects::MachNo MachNo(U) failed to execute"

Any help is appreciated to compute the Mach number.