[hansenka]

There are several posts about natural convection in this forum, but none of those solves my problem.


I have created a 2D 0.5m high small "scale" and model for a case, with partly heated wall. There is one inlet and outlet.
This is a k-epsilon model using perfectGas and buoyantSimpleFoam as solver, for air.

Boundary conditions, system folder and velocity profiles are attached in this post. if you want to run the case, I have to create a blockMesh, My mesh exeeds the storage limit.



The problem I am struggling with is negative flow at inlet (left picture). The U_magnitude is positive, but both U_X and U_Y are negative and U_Z is zero. The outlet flow (right picture) is positive, resulting in a constant loop of the model and after 100k+ iterations, the model crashes.

How do i manage to add a positive inlet flow to the model? I have tried different approaches with outletInlet for U, p_rgh and T + many other approaches, without any success . What fixed mye positive outlet flow was setting T_outlet to inletOutlet.

pressure is calculated using: p = p_rgh + rho*gh + pRef. p_rgh is pressure without hydrostatic pressure.

p_rgh diverges, which is a common problem in this forum.

QUICK scheme have been used to discretize the momentum and energy equations, without luck. (Litterature study suggest using QUICK scheme for the mentioned eq's)


Any help solving this back flow problem?