flow over 4 airfoils -2D case
 

I am trying to simulate flow over 4 airfoil one kept in the wake of another airfoil in 2D case. Rectangular domain is taken as the flow domain with K-omega model with polyhedral mesh.
Chord length c= 0.605m
Top and bottom surface = 5c -(symmetry plane)
inlet velocity =109 m/s
outlet = Pressure outlet
I am not able to get the predicted flow output. I hereby attach the velocity scalar scene of the flow. From the plot it can seen that the velocity far away from all the airfoils is different from the inlet velocity. I have no clue why is it happening. Shouldn't the velocity near the bottom and top wall be inlet velocity?.It would be grateful if anyone could help me figure out the problem.