[cshsgy]

Hi all,
I have recently encountered a strange problem that troubles me a lot. I am running a two-phase case the involves particles and air. The geometry is simply a 2D slice of a cylindrical body.
The simulation is done with variable time step with Courant Number smaller than 1, so the problem is discovered that deltaT suddenly drops to an extremely low level after simulating for a while, which means the Courant Number actually blows up at that position.
To simplify this problem, I forced the volume fraction of particles to be 0, so what is simulated is actually a single phase flow.
The problem happens at around 1.5s of simulation, and the velocity field is attached: before and after the blowing up of Courant Number, nearly all quantities behave quite well, including k, epsilon, velocity, etc. The only observable irregularity is observed with the pressure field. Pictures of the velocity field and the pressure field are attached.
I appreciate it a lot if you could be helping me, since it has really troubling me for quite a long time.
Thanks a lot guys!