[Marcel95]

Good morning,

i am simulating a freejet of hydrogen in still ambient air and want to validate the results with experimental data.

Gas-Components are Air and H2 (these to gases are very different in density).

The model is isothermal and i use the ideal gas equation (frist i had a van-der-waals gas but i read here in the forum that bouyancy effects in starccm+ only work with ideal gas + gravity or with a constant density model)

Gravity is activated to -9,81m/s^2 in z-direction.

It is a steady simulation.

The problem is that i still have no buoyancy effects. There should be one bacause of the large difference in density (according to multi component gas, not because temperature differences).

Anyone an idea?