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sophie_l April 19, 2013 11:24

water velocities (point data) are all zero
Hi there,

I ran a case using interFoam. The mesh is 2D (only one cell in the z direction). Y-axis is 4 m high, 0-2m is water and 2-4 m is air. The free surface (using alpha1) looks good in paraview. But when I choose U-magnitude (point data) for animation, only the inlet patch and the top of air have non-zero velocities. When using U-magnitude (cell data), the water velocities are non-zero and look normal.

However, I need to extract the water velocity at sampling points or over a line to do some comparison. I cannot save the cell data via 'plot over line', only point data are saved, ie., water velocites are all zero. It is really strange to me. I am thinking maybe there is something wrong with the settings in paraview as the output U files are of non-zero values. Could someone shed some light on this please?

Thanks a lot in advance.

ngj April 20, 2013 03:50

Hi Sophie,

Maybe you could use the OpenFoam utility "sample" instead. This allows you to sample along a given line.

You can find more information and an example of the needed dictionary here:


Kind regards


sophie_l April 20, 2013 06:08

Hi Niels,

Many thanks for your guidance! I'll try it.

Best wishes,

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