this behaviour have no explanation for me as you said there's enough compression/expansion of the flow to divert the particles. In this comparison (k-epsilon and k-omega cases) I used 100 stochastic tries.
Even if i use more tries, like 1000 it looks the same, where the particles doesnt even get close to the wall for the k-omega model.
100 tries, using time scale 0.3 suggested in others post for k-omega
1000 tries
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