Solar chimney simulation

Hi

I'm currently doing a project on solar chimney and how they can be used in a house. i chose to do the simulation on solidworks but i'm having some trouble setting up the boundary conditions properly. At first i used environmental pressure at all openings but this is creating a vortex and the results doesn't appear to be good.

Any suggestions on how to proceed with this simulation is welcome.

SolidworksFlow Simulation