[Gfs-users] How to solve divergence problem

[Li]

Hello, all

       I am using Gerris to simulate impinging jet atomization process. As in the ‘Atomisation of a pulsed liquid jet’ example, I set up velocity inlet boundary conditions with sine velocity inlet. The simulation was fine in two velocity cycles. But on the time about two cycles, the simulation diverges abruptly. The pressure and velocity at some points were soaring abruptly. Then it came out 'CFL number at some point is larger than 0.51', and the simulation crashed. I have tried many methods to solve the problem. I removed droplets smaller than 9 cells. I also tried dimensionless calculation. But the problem was still not solved.  

        Have you ever encountered the same problem? Or can you give me some suggestions to solve the problem? I have been confused by the problem for so long a time, and it would be grateful if you would be so kind to help me to solve the problem.

       Kind regards,

       James Li