Hi, everybody,

My problem can be described as: an object is driven to move within a chamber due to a flow passing through this chamber at some specific time. Apparently, this is a transient problem. It seems the sliding mesh won't work for this case because the sliding mesh approach requires the grid interface must to be situated such that there is no motion normal to it. The vertical dimension of this object is larger than the vertical dimensions of both the inlet and outlet of this chamber. So if I use the sliding mesh, the grid interface will inevitably cross the wall of the chamber.

Any suggestion will be highly appreciated!

Whitaker

Hi, I have a similar problem solving a rotor-stator with the rotor blade meshed. I'm waithing for an answer form fluent and i'll post that to you.

Pierluigi Allegro

Dear Whitaker

As far as my experience is concerned, I've met fairly difficulaty situation for the convergence problem of energy equation for every simulation. It may be dependent of case by case. But I could obtain converged solution by adjusting under-relaxation parameter for energy equation for most case. I usually use underrelaxation parameter, 0.7-0.8, for start-up and increase step by step and eventually near 1.0. Then, it was O.K. for most cases.

I hope it will be helpful to you.

Sincerely, Jinwook

Dear Jinwook,

It seems this message was written for some people else. Anyway, thanks a lot.

Whitaker

Thanks for your reply. By the way, do you think it is a good idea to solve my problem using VOF? Just treat the solid object as another fluid with very large viscosity.

Whitaker

Dear Whitaker

I am very sorry. It's reply for 'convergence....', another item.

Sincerely, Jinwook