Overwrite velocities

March 9, 2011, 03:20

Hi!

I'm trying to add a damping term to the velocities in a given region.
Do someone know if it is possible to overwrite the defined velocity variables (u,v,w) used in the solver?

I would like to dissipate the velocity gradually by a damping function.
In CEL it was not possible to do something like u = if(x>=xstart,u*damping,u),
since u is already a defined variable.

Maybe a user routine can do this?

Regards.

ghorrocks · March 9, 2011, 18:49

If you want to add some damping try a porous region with a small resistance. Alternately you can define a source term and do what ever you like - either damp it a little or specify the velocities or anything else you can dream up.

March 9, 2011, 03:20	Overwrite velocities	#1
Jarle Guest Posts: n/a	Hi! I'm trying to add a damping term to the velocities in a given region. Do someone know if it is possible to overwrite the defined velocity variables (u,v,w) used in the solver? I would like to dissipate the velocity gradually by a damping function. In CEL it was not possible to do something like u = if(x>=xstart,u*damping,u), since u is already a defined variable. Maybe a user routine can do this? Regards.

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March 9, 2011, 18:49		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	If you want to add some damping try a porous region with a small resistance. Alternately you can define a source term and do what ever you like - either damp it a little or specify the velocities or anything else you can dream up.