Hi,

Can you help on a problem of heat transfer on complex geometry. I'm modelling on Fluent an enclosure (3D) with sidewalls heated by a time-dependant profile and with one opening. Under effects of heat, the fluid inside this grows and flow through the one opening. The aim is to determinate the mass flow rate and the evolution of temperature at the outlet. My problem is what are the boundary conditions i must to put in the surface outlet (between pressure inlet, pressure outlet or outlet in Fluent) regardless i don't have the temperature at the oulet (which must be determined by the simulation). Thanks for your answers!

use outflow boundary condtions .

Thanks for your answer! But do you think it's not a problem as the fluid has temperature-dependent properties and it is unsteady formulation.

Best regards!