This is an odd one.

I'm attempting to set up a simulation with solidworks flow simulation that is essentially modelling the flow of air though a greenhouse-like structure.

So the boundary conditions are all set to environmental pressure, and the only source of energy is solar.

The results of the simulation are entirely believeable, that is the trajectories and turbluence seem right: except that the direction of the airflow appears to be exactly opposite to what I would expect.

Rather than air entering the greenhouse at the base and flowing upwards, it's entering the top of the greenhouse and flowing downwards!

What have I missed? I have attached an elevation view of the greenhouse structure. It is open at the left and right verticals, and at the verticals under the 'eaves' (so environmental pressures at all vertical elements shown in the elevation view.) Also attached is a detail showing the direction of airflow - downwards??

It looks like air is rushing down the 'chimney', and out the base...

I am eternally grateful for any assistance in working out what the heck is going on here. Also attached is the SLDPRT file.

Thanks in advance,

Al