[Fari87]

Dear all,

I'm doing some investigation on natural convection arround solids. In this case I've modeled a cylindrical solid, which needs to be rotational accelerated to 1000 rpm. There shall be a viscous flow and I'm using the k-omega-model. As I believe there is no acceleration possible in fluent (please correct me if I'm wrong) I'm trying to solve the issue with an UDF.

Actually there is an example in the "fluent UDF manual" available as I've pasted below. I've successfully interpreted this code in "cell zones" to the mesh motion of my solid:

#include "udf.h"

DEFINE(fmotion,omega,axis,origin,velocity,time,dti me)
{
if(time<1.5)
{
*omega=2500.0*time;
}
else{
*omega=250.0;
}
N3V_D(velocity,=,0.0,0.0,0.0) /*No translational velocity applicable*/

return;
}

To my question:
How do I include the shadow walls (boundary conditions) to this code? My understanding is that the cylindrical solid and corresponding shadow walls from the contact region need to have the same angular velocity to enable heat transfer.

Thank you very much in advance for your support.

Best regards,
Fari

[Fari87]

hi all,

any ideas regarding this case? I would appreciate every hint to solve this problem...

thanks and kind regards,
Fari