Problem with probes at boundary
 

Hello,

I'm currently running a acoustic tube simulation with the rhoPimpleFoam solver.
The model contains only cells arranged in x-direction. The faces in y- and z-direction are empty. On the left side I'm using a oscillatingFixedValue boundary where the amplitude of Ux oscillates around zero. The boundary on the other side should not bother because it is far enough away.

And here comes the problem:
I'm using probes at given distances and found out that the probe of Ux at the oscillating boundary differs pretty much from those more in the middle of the pipe. At the boundary the mean-value of the oscillation rises above or below zero over time depending on the x-position while in the middle of the tube is oscillates around zero like it shout be.

In contrast to this mentioned above, if I look at the results via plot over time in paraview at the first cell the magnitude of Ux oscillates around zero.

It seems that after 100 Cells the probes work proper and Ux oscillates around zero. So I think there must be some problem with the probes output. :confused:

Does anybody had the same experience and in the best case some informations and/or ideas to get the probe at the boundary working right?

Thank You!