hi,All: I build a model of moving mesh.A fan in a channel in this model.I use the ASI method to simulate the situation.Besides,unstructed grid is used in the fan and structed grid in the channel.But the solve is always divergence.I think the scale of time and grid is enough.Are there another reasons for the divergence? Please tell me. Thank you.

check relaxation factor and residual tolarence....run ur analysis with reduced those parameters

you might have to underrelax the piso algo:

algo piso node 20 0.15 0.7

additionally you should use switch 60