[Max0139]

Problem: Paraview skips umean data for some timeframes.

Hello CFD-Online,

I am a new OpenFoam user and I am just starting making DSMC simulations. I have a problem with the visualization of the UMean in paraview. Almost all of the data I load is shown correctly except for the average velocity UMean. I used the supersonicCorner tutorial to reproduce the problem. The original tutorial case works perfectly, even when I change the timesteps in the controlDict. However, when I change the geometry (see below) in the blockMeshDict to a more triangular shape, paraview seems to skip some of the timeframe/steps for the umean plot. The UMean plot works for the first few timesteps but then the geometry turns gray and no results are shown. After that, the simulation continues plotting the UMean after another few timeframes/steps as if nothing has happened.

Does someone have the same issues or knows how to fix this? I hope that someone can help me with this.

Kind regards,

Max

Specs.:
OpenFoam 3.0 for Windows (laptop can't handle Ubuntu)
Paraview 5.0.0 64-bit

Changes to blockMeshDict:
change the coordinates and amount of cells in z direction to get an almost 2D like shape in order to lower the resolution time. (had no effect on the UMean plot)
change the block on the right hand side to a triangle by moving the points in the upper right corner to the left in the blockMeshDict as described in the manual.
After this my blockMeshDict looks like this:

convertToMeters 0.01;

vertices
(
    (0 0 0)
    (5 0 0)
    (5 18 0)
    (0 18 0)
    (0 0 1)
    (5 0 1)
    (5 18 1)
    (0 18 1)
    (30 0 0)
    (5 18 0)
    (30 0 1)
    (5 18 1)

);

blocks
(
    hex (0 1 2 3 4 5 6 7) (10 36 1) simpleGrading (1 1 1)
    hex (1 8 9 2 5 10 11 6) (50 36 1) simpleGrading (1 1 1)
);

//* I didn't change anything other than the timesteps and the above mentioned values in the blockMeshDict.

[Max0139]

I think I found a solution to my own problem. I noticed that, when running the simulation, the OpenFOAM prompt shows the following message when writing the fielddata:

Small value (min(mag(rhoNMean)) [0 -3 0 0 0 0 0] XXX) found in rhoNMean field.
Not calculating dsmcFields to avoid division by zero.

I only got this message for the timesteps that don't show UMean (and probably other average values). When I googled message I found the following thread: http://www.cfd-online.com/Forums/ope...lculating.html. Here, a solution for this problem is given. (I didn't find this thread before since I didn't notice the message in the OpenFOAM prompt which I used to find this one)