Flow over 4 airfoils in STAR-CCM+ -2D case
 

Hi

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. After some time, there is zero velocity zones in the domain. I have no clue why is it happening. It would be grateful if anyone could help me figure out the problem. I hereby attach the velocity scalar scene of the flow.
Thank you in advance

How many iterations? What do your residuals look like? How are you initializing the solution?

You need to provide more info.

time step = 7.989*10^-5
the problem happens after around 0.5sec
the residuals converge upto less than 10^-4