Reply To: How to make my simulation converge?

[Rob]

That looks more reasonable. Zoom in on the jet and replot the velocity contour with node values off.  That'll help show if you have sufficient resolution of the jet, no need to post images, it's for your learning. 

I'm not sure if you need the solid region. Unless it's deforming I'd use a thin wall but make it "thick" using the Fluent boundary options. If you do want it, set as solid in Fluent Meshing and let the meshing tools do the work. I'm not as familiar with the functions so can't really advise further.