Impinging Jet Modeling Problem
 

I am trying to model an impinging jet . There is a nozzle through which air is exiting vertically downwards and hitting the ground. I have two questions about it.

1) what would be the top boundary condition besides (next to) the inlet? Is it pressure or Inlet with zero U and V velocities? If I put Inlet condition bc there with zero U and V , then what values do I put for k and epsilon there ?

2) What are the values of inlet turbulent kinetic energies and dissipation which I need to specify for the inlet jet using k-epsilon model? I am using both FLUENT and STARCD for analysis.

Thanks