Learning Forum

[Nicolas Oneto]

I am designing a ramjet for fun. I have simulated supersonic flows (density-based, k-epsilon, ideal-gas, pressure-farfields as boundary conditions, etc.) Now, I need to simulate the reaction, and the only model allowed when using density-based is species transport. I turn on volumetric reactions, eddy-dissipation, and hydrogen-air species. I keep getting these errors with these settings, and I do not know how to fix them. Any help will be greatly appreciated. First picture is the cross section of engine and second picture is the errors.

[Rob]

It's diverged. So, you need to review the mesh (cell quality and resolution - ie are you capturing all of the combustion species gradients), boundary conditions (are they sensible) and physics (is the combustion model sensible) and see if the model should be stable and work.