How to impose a Pulsating Flows as a boundary condition in COMSOL ?

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Muneer Ismael

Dear Kaid Noureddine ,

Yes it is possible. Firstly, you should set your problem as Time dependent one. In the inlet boundary condition of fluid, you can select "velocity". In this field you can give the expression of the time dependent velocity. The attached photo may help you.

Regards.

Kaid Noureddine

Thanks a lot Muneer Ismael

I will try this, but what about if it is as follow : uo=cos(pi*t) ????

It gives more sense, is it ? !!!

--------------------Simulation....

It works as : v0*cos(t*1[1/s])...

You're very helpful ...

Yes, you are wright!

In my previous photo is only to show how you input the boundary conditions.

As you suggest, you can include the frequency (pi) and the amplitude of the pulsating velocity (Vo).

Best Regrads

Hi Muneer Ismael

I have edited my latter post and added a screen shot of the resolved problem...

It works pretty fine...

My very best regards