[andrea.pasquali]

Hi,
I'd like to simulate the thermal anlysis of a car.
I'm thinking to use the solver "buoyantBoussinesqSimpleFoam".
I saw the post:
- http://www.cfd-online.com/Forums/ope...am-solver.html
- http://www.cfd-online.com/Forums/ope...planation.html

I have some question:
1) Is it possible make what I want with "buoyantBoussinesqSimpleFoam"? Or I'm wronging solver?
2) Is it correct to simulate the heat flux of the engine like a fixedGradient for the Temperature? In this case I need the alfa_eff of the engine! If it exists, does anyone know a stardard value of alfa_eff for an car engine?
3) If I have the correct heat flux of the engine, could I use the BC "wallHeatFlux"? Do I set it into T file?

Before to try with the car, I'm training myself with a simple model: a hot sphere into a room.
I tried before a closed room:
T: initialField 298, fixedGradient for the sphere, zeroGradient for the walls
p: buoyantPressure for all
U: fixedValue (0 0 0) for all
Then I tried to add an inlet in front of the sphere and an outlet in the back side of the sphere:
T: initialField 298, fixedGradient for the sphere, zeroGradient for the walls, inlet and outlet
p: fixedValue 0 for the outlet, buoyantPressure for the other patchs
U: fixedValue (1 0 0) for the inlet, inletOutlet for the outlet, fixedValue (0 0 0) for the other patchs

But I obtain a strange result.
The map of pressure and velocity in a section is not correct: I have over pressure near the inlet and big velocity near the outlet.
My results are quite similar to the results showned in the posts above!!!
Therefore, I made some stream lines: they start straight and when overcome the sphere, they turn on the right!
I though the error was on inlet / outlet BCs! So I started changing the BCs first for inlet and outlet and then for all the patch (I tried also the slip type for the wall) and I entered in a blind loop!

Could anyone give me any suggestion?

Thank for any reply!

Andrea