I am not really sure but I think in most cases it is common to simply use the velocity of the cell closed to the wall for the wall face itself. Another option is to calculate wall shear stress vector (http://www.cfd-online.com/Wiki/Wall_shear_stress). This could also be helpful for surface restricted streamlines.
Regards Andy Bauer schrieb: > I don't know of any existing filters that will try to do this for > you. You may have to write your own custom filter for it. What > algorithms are used to calculate these pseudo velocities at the wall? > > On Tue, Jul 7, 2009 at 5:20 PM, [email protected] > <mailto:[email protected]> <[email protected] > <mailto:[email protected]>> wrote: > > Andy Bauer schrieb: > > I'm guessing that the simulation is using no-slip boundary > conditions > > (i.e. setting the velocity to be zero at walls). > Correct, yes > > Are you sure that there should be non-zero velocity at the walls? > > Is there non-zero velocity elsewhere in the domain? > No there should not be non-zero velocity at walls. Zero is correct. > However in certain circumstances it may be interesting to get "pseudo" > velocities at walls - eg. to calculate surface streamlines or make > contour plots of velocity magnitude "directly at" the wall. > Therefore I > want to interpolate some velocity values to the wall as other > postprocessors can do. > > > > On Tue, Jul 7, 2009 at 2:50 PM, [email protected] > <mailto:[email protected]> > > <mailto:[email protected] <mailto:[email protected]>> > <[email protected] <mailto:[email protected]> > > <mailto:[email protected] <mailto:[email protected]>>> wrote: > > > > Hi all, > > > > I do an export from my CFD code using node-values. I get the > value of > > "0" for the velocity at walls in Paraview. I can not > visualise contour > > of velocity magnitude at the surface or do surfaces streamlines. > > How can > > I get velocities to wall boundaries? I tried calculation cell > > values and > > point values once again, however I still have zero velocites > at walls. > > > > Thanks BastiL > > _______________________________________________ > > Powered by www.kitware.com <http://www.kitware.com> > <http://www.kitware.com> > > > > Visit other Kitware open-source projects at > > http://www.kitware.com/opensource/opensource.html > > > > Please keep messages on-topic and check the ParaView Wiki at: > > http://paraview.org/Wiki/ParaView > > > > Follow this link to subscribe/unsubscribe: > > http://www.paraview.org/mailman/listinfo/paraview > > > > > > > ------------------------------------------------------------------------ > > _______________________________________________ > Powered by www.kitware.com > > Visit other Kitware open-source projects at > http://www.kitware.com/opensource/opensource.html > > Please keep messages on-topic and check the ParaView Wiki at: > http://paraview.org/Wiki/ParaView > > Follow this link to subscribe/unsubscribe: > http://www.paraview.org/mailman/listinfo/paraview > _______________________________________________ Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview
