CCM+ HELP! I'm trying to simulate natural convection from a heated fin into air. The air density and temperature around the fin vary as expected, but there seems to be no air movement. The model is setup with a solid continuum and a fluid continuum. The model for the fluid is as follows: Steady, Laminar, Segegrated Fluid energy, Segegrated flow, Gravity, Ideal Gas, 3D, Static, Gas.

I'm probably missing something simple, but any help would be great. Thanks.

check gravity direction and run in double precision

Wouldn't the temperature field in static air be much different to the one in moving air? So if you're getting the right temperature field, the air must be moving? Maybe it's just a post-processing glitch. Can you see that the velocity magnitude is exactly zero, or are the vector arrows just very short?

The gravity is on, but not sure how to run the model in double precision in CCM+. Can you tell me? I've checked the postprocessing over and over, both graph plots and scalar/vector displays. Both read no velocity. Thanks guys

You would need to download a separate double precision version. Have you tried the coupled solver instead of segregated?

Coupled solver comes up with an error message, telling me: "Error: attempt to access nonexistant TemperatureSource field on cells" Does this mean anything to you?