Convergence at high Velocity

Hello,

I am trying to develop a model of nozzle flow into a cavity. I have a model that I am able to run at low velocities (0.1 m/s), but have not been able to get a higher velocity (~50 m/s) version to converge. I've attached an image of the result I get from the 0.1 m/s model. Do you have any suggestions?

Thanks,
Trevor