[helloworld11]

Hi everyone,
I am quite new to OpenFoam world and I need some help. I would like to calculate average values of velocity and pressure on my boundary patches. Any idea how can I do it? Any help will be appreciated

[bigphil]

Hi,

You could use the patchAverage and/or the patchIntegrate post processing OpenFOAM utilities.

For example, to calculate the average pressure on a patch called myInlet:

patchAverage p myInlet

Philip

[helloworld11]

Hello Philip,
Thank your for your answer. I just tied patchAverage p inlet for my case works fine.
But for the velocity values if type patchAverage U inlet, I get the error :

Only possible to average volScalarFields

Is there any way to over come that error?

[bigphil]

helloworld11,

patchIntegrate and patchAverage only operate on volScalarFields, so if you decompose your velocity field into its components first using foamCalc, i.e.

foamCalc components U

Then you can run patchAverage on each component:

patchAverage Ux myInlet

You can also use foamCalc to do other things like calculate the magnitude of a volVectorField:

foamCalc mag U

If you type something like "foamCalc banana" it will give you all the options.

Philip

[helloworld11]

Philip,

I followed the instructions you gave and now I am able to get values. Thank you very much.

[Vishsel]

Hi all,

Again i am initiating this old thread to find the average field values of two or three patches ..

Any command to measure the field average values of totally three patches ??

like three patches namely - inlet1,inlet2,inlet3 .. I need average value for three patches ..

Thanks in advance,
Vishsel

[lumasci]

Originally Posted by bigphil

Hi,

You could use the patchAverage and/or the patchIntegrate post processing OpenFOAM utilities.

For example, to calculate the average pressure on a patch called myInlet:

patchAverage p myInlet

Philip

Hi, how do you setup myInlet in 0/U or 0/p?
In my case, I want to create an 'artificial' patch in order to get a mapping of the velocity for this specific area.

Usually, I use paraview/cross section to achieve that, but in this case, the geometry is much more complex. Therefore, I want the value of the velocity in this patch.