I hope the figure below helps:

a. Meshing: I have attached an image for your reference. Please take a look.

b. I have a quick question regarding cavitation. I discovered that the Zwart-Gerber-Belamri and Schnerr and Sauer models are compatible with all the turbulence models available in ANSYS FLUENT. Since my flow is turbulent, using any K-E or K-W model will affect the results for cavitation.