Reply To: Spray Cooling Residual Values Blowup! Help!

[Judy Cooper]

Hi Greg:

If it is blowing up at a certain iteration, I would try to stop the run just before then and take a look at the solution in detail.  With particles, the isues can come from many things.  Unfortunately, with transient operation, there are not as many underrelaxations that you can do, so your only option is generally to reduce the timestep.  If it is possible to inject more representative particles for the spray, this may be beneficial too.

Expanding the box around the plate may help to stabilize the boundaries because conditions there are more likely to be predictable, (ie: ambient temperature with little flow).  A hemisphere type boundary shape may help to give a better mesh and prevents directional wierdness at corners.  Flow at the boundaries should come back in from nearest cell and not normal to the boundary.

I hope this helps,

Best Regards,

 

Judy