Konstantine Kourbatski
Ansys Employee
for reporting convective CFL, you can temporarily switch to the pressure-based solver which has convective CFL under velocity. No need to run the solution in pressure-based to inspect the CFL.nRequirement to maintain convective CFL ~ 1 (and acoustic CFL if you are interested in acoustics) is pretty much universal across CFD solvers. The implicit density-based formulation allows you to run with larger CFLs but at a cost of loosing transient information due to numerical dissipation and potentially arriving to a wrong answer. Very large CFLs can also lead to stability problems, as you are observing.nBut as long as you understand the trade off between larger time step and accuracy/fidelity of the solution, you ca try larger steps.n