A numerical study of under expanded jet and impingement on a wall mounted at various distances from the nozzle exit is presented. The 3-dimensional Navier-Stokes equations and k-ω turbulence equations are solved. The grids are constructed as overlapped grid systems to examine the distance effect. The DADI method is applied to obtain steady-state solutions. To avoid numerical instability such as the carbuncle phenomena that sometimes accompany approximate Riemann solver, the HLLE+ scheme is employed for the inviscid flux at the cell interfaces. A goal of this work is to apply a number of two-equation turbulence models based on the ω equation to the impinging jet problem.