Time averaged values

General Discussion
1

Hello forum,

I am trying to get the mean values of an unsteady flow. So far I tried the following code:

for (i=1; i<=iterations; i++)
{
t +=dt; // update the time step
up[ ]=u[ ]; // Problem variables
PROBLEM; //Call to solve the problem equation
sumu[ ] += u[ ];
}
umean[ ] = sumu[ ]/iterations;

The problem is that “sumu[ ] += u[ ]” doesn’t seem to work as I expected. For example if at iteration “n”, the maximum velocity is 1 m/s and at iteration “n+1”, the maximum velocity is 2 m/s, I get a maximum velocity of 5 m/s.

I attached the equation of the time integral which I want to apply now in this case in order to get the mean/time-averaged values. Unfortunately I didn’t manage to implement it.
image

Could you, please, help me to get the mean values?

Regards,
Robert

2

That should work, do you do some kind of mesh adaptation?

3

Hello prj, and thank you for the fast answer. No, I don’t adapt the mesh.