unit of U in paraviewer?
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unit of U in paraviewer?
Hi guys, I get crazy high values in my simulation to the power of 14 while the outlet speed set is only 5m/s? so my question is if im doing anything wrong or whats the unit of U
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Re: unit of U in paraviewer?
openFOAM uses SI units.
See U/p files after case writing.
EDIT:
the results shown in paraview correspond to openFOAM.
https://www.cfdsupport.com/openfoam-tra ... ode51.html
https://doc.cfd.direct/openfoam/user-gu ... ile-format
See U/p files after case writing.
EDIT:
the results shown in paraview correspond to openFOAM.
https://www.cfdsupport.com/openfoam-tra ... ode51.html
https://doc.cfd.direct/openfoam/user-gu ... ile-format
Re: unit of U in paraviewer?
So the U in paraviewer is actually dynamic viscosity and not velocity?thschrader wrote: ↑Wed Jul 06, 2022 4:28 pm openFOAM uses SI units.
See U/p files after case writing.
EDIT:
the results shown in paraview correspond to openFOAM.
https://www.cfdsupport.com/openfoam-tra ... ode51.html
https://doc.cfd.direct/openfoam/user-gu ... ile-format
dimensions.JPG
Re: unit of U in paraviewer?
No, U ist velocity with the dimension [m/s]
Re: unit of U in paraviewer?
Yes, in Paraview you can chose "U", then the approriate colour corresponds to velocity U. And as Thomas wrote OpenFOAM takes SI-units, in this case [meter per second or m/s]. Or you can filter for Glyph in Paraview to show the velocity-vectors. But you must play a bit around to find the best relation of Glyph-size to velocity.
Re: unit of U in paraviewer?
Example 2D CFD:
This animated .gif shows what I mean. The fine lines are streamlines, the colour shows the velocity, or more precise the changes of velocity.
But I do not know what the flash-like artefacts are and where they come from. Not nice but no influence on the results.
This animated .gif shows what I mean. The fine lines are streamlines, the colour shows the velocity, or more precise the changes of velocity.
But I do not know what the flash-like artefacts are and where they come from. Not nice but no influence on the results.
Re: unit of U in paraviewer?
Even if your simulation had somehow gotten set to nm/s (unlikely), you would still only be seeing 10^9 or so. Sounds like your simulation diverged/blew up. Did you use a velocity inlet? You can get weird results if there's nothing to bound the pressure. Or you might have used too large of a timestep, or had bad mesh elements somewhere. It's hard to say without more information on your simulation.