Flow in a circular tank
 

I am trying to simulation the flow in a circular tank , flow in injected at the top and outlet at the bottom. I have try to check some previous msg in this forum but I didn't find a similar simulation (including the one in the FLUENt tutorial tank.zip). I would like to know if I am using the right parameters in my simulations

Simulation case : Physical description : Circular tank Diameter=: Dt , free surface (atmospherique pressure ) liquid inject from the wall near the free surface and outlet at the bottom of the tank exactly in the middle (Diameter Do < Dt).

Numerical Description (FLUENT): -Tank : wall. -Inlet : Inlet velocity, Turb Spec Method = k-eps Material : water. -Free surface (Y_freesurface) : wall, roughness =0 , no slip.(as it is adviced in several post(?)/or shall I use symtery?) -Outlet : pressure outlet , gauge pressure = 0(Pa), Radial Equilibium Presuure Distribution, Turb Spec Method =k-eps -Operating Conditions : Operating pressure =101325 (Pa), Ref Pressure Location = Y_freesurface, No Gravity. -Turbulence : k-eps, standard wall function -Steady simulation.

I am not sure about the Oulet (pressure outlet ? or smthg else ?(I am using water)/Do I need to take care of the hydrostatique pressure (column of 3,5m of water). Do I need Gravity?, Is it right to define Ref Pressure Location at the top of the tank(free surface). Thanks for your help