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-   -   Ensemble average for oscillatory flow in OpenFoam (https://www.cfd-online.com/Forums/openfoam-solving/116812-ensemble-average-oscillatory-flow-openfoam.html)

 kobelak April 25, 2013 11:13

Ensemble average for oscillatory flow in OpenFoam

Hi guys!

This is my first post here. I googled my problem a lot of times but I didn't find anything about this topic neither here nor in other web sites.
I'm simulating a turbulent oscillatory flow in a channel with my own modified solver based on channelFoam solver. The flow is driven by a periodic pressure gradient, therefore the velocity is also periodic for a given point in the domain.

Now, I'd like to calculate the Umean field, but I cannot use the normal fieldAverage library: since the flow is oscillatory, averaging based on time is useless, and I should use an ensemble averaging.

In substance, I want to calculate the arithmetic mean of the velocity for each phase of the periodic flow. For instance, if the duration of the simulation is 4*Period, U_mean for phase = 0° is:

(U(1st Period, phase = 0°) + U(2nd Period, phase = 0°) + U(3rd Period, phase = 0°) + U(4th Period, phase = 0°))/4.

I'm thinking to modify the fieldAverage code in order to calculate what I want, but I don't know how. I can look into the code, but I'm not able to modify it. Does anyone have a better idea? Did anyone try to do anything similar? Could you give to me any hints please?

I'm using OpenFoam 2.0.1.

Danilo

 kobelak May 22, 2013 04:59

Hi guys!

It seems that this problem is just mine! Anyway, I read that release 2.1.1 of OpenFoam can do an ensemble averaging in post-processing.
Unfortunately I don't have the opportunity to test this new release now, so does anyone use this feature yet? Could it be the solution of my problem?

Danilo

 Thangam July 22, 2014 06:33

Hi Pietro,

Did you manage to solve this issue? I am facing this as well!

Thanks.

Thangam.

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