[Stephan_CFD]

I'm simulating a stirred reactor filled with water that has an impeller with 4 blades, equally spaced with 90°. Reactor has 4 baffles, equally spaced as well.
When I analyse torque over time of the rotating impeller, I see 4 spikes of the torque for each turn of the impeller, which is what I expect because of the interaction impeller blades/baffles. However, When I plot mean flow speeds Vx, Vy of the fluid I find only one peak per impeller rotation. I would expect the same as for the impeller itself. So therefore the flow speed output for the fluid doesn't make sence.

Anyone here who has observed similar issues?