I am a newer for Fluent. I want to model the coating process with Fluent( I know FIDAP works this problem, but I don't have FIDAP available.)

I set the BC of free surface as pressure inlet, the BC of fluid into the coater as pressure inlet, the substrate as a moving wall and the left BC as outlet. Then I patch a volume of air arbitrarily as the initial phase arrangement and run with unsteady state and zero velocity for all the fluids. However, every time the error is floating point exception(underflow). I don't know how to deal with it.

Many thanks. I'm looking to hearing from you.

qb Jiang

Hi,

did you mean you set your outlet as an OUTFLOW?. If so, try changing to PRESSURE-OUTLET. Also try PRessure Inlet to Velocity Inlet if you have the velocity profiles at the inlet.

Check the grid as well!

Cheers mm

Hi, Thank you for your reply.

I had these tries, but it still doesn't work. I don't know why. I set the outlet as velocity inlet, change the pressure inlet into velocity inlet. There is nothing wrong with the mesh. I wonder if the problem lies in that the dimension is too small(50-220 micro)?

Qibo