Vorticity contour for falling sphere?

govind_sharma · September 23, 2020, 4:35am

How do I plot vorticity contours for a falling sphere in fluid which is initially quiescent.

mwestphal · September 23, 2020, 6:47am

please share your data.

govind_sharma · September 23, 2020, 8:49am

The figure in above is from Vislt. I want to get something this type of plot.
Here are the data files. I have run in parallel (4 procs) but data from two will be fine I think. foam1 is from processor 1, foam2 processor 2 and these two have relevant CFD data and solid is for sphere.

foam1.csv (2.1 MB) foam2.csv (2.1 MB) solid.csv (178 Bytes)

Kenichiro-Yoshimi · September 25, 2020, 1:45am

Hello,

There is one of the ways to calculate a vorticity vector:

Load foam1.csv > Table To Points Filter (TableToPoints1)
In the same way, load foam2.csv > Table To Points Filter (TableToPoints2)
Use the Append Geometry filter to merge TableToPoints1 and TableToPoints2 to a single point cloud.
Use the Clean filter to remove duplicate points.
Add the Delaunay 3D filter to turn a point cloud into a continuous volume.
Use the Calculator filter to create a velocity vector: iHatU_0+jHatU_1+kHat*U_2
Use The Gradient Of Unstructured Data Set filter to calculate vorticity from velocity vector.

Here is a ParaView state file that replicates the above.
vorticity.pvsm (1.1 MB)

govind_sharma · September 25, 2020, 10:21am

Thanks Kyoshimi,

I tried what ever you stepped out . With same pvms file, I do not see vorticies but I can visualize other like u_0, u_2. I took screenshot just after loading in pvsm.

I followed myself to generate the visualization pipeline I get the error for filter “gradientOfUnstructureDataset”.

In this case I do not see anything.

Kenichiro-Yoshimi · September 25, 2020, 11:29am

Hello,

In loading a pvsm, would you hit the eye icon on the left side of GradientOfUnstructuredDataSet1 in the pipeline browser?

govind_sharma · September 25, 2020, 12:03pm

I got it with pvsm. Actually I did just refresh the dataset and I can see. But its not smooth one (may be because of grid size I will check that if its).

If I want to see line contours of vorticity then how do I do that?

And when I setup pipeline myself I get the error for filter i.e. second image above.

Kenichiro-Yoshimi · September 28, 2020, 7:31am

Hello,

Some additional steps might be required to see contour lines:

Use the Calculator filter to extract y-component from a vorticity vector: Vorticity_Y
Apply the Slice filter to cut a volume with a symmetry plane: Origin(0.625, 0.625, 5), Normal(0, 1, 0)
Use the Contour filter to to grab contours.

This is a state file:
vorticity1.pvsm (1.4 MB)

And when I setup pipeline myself I get the error for filter i.e. second image above.

I’m afraid that I have no idea why the error occurs.