flow over a cyllinder

Madhukar Rapaka

Hi, I am simulating flow thru a 2d- finned heat exchanger. In this heat exchanger there are circular cylinders, which are placed like /\

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\/ (at the top end of each slash'/ or \'there is a circular cyllinder and also at the bottom end) first i am starting with a laminar case and using this solution in modelling a tubulent flow. The solution is converging very fastly. But when i look in to the velocity contours...at the top and bottom of each cylinder the velocities are very high. Is this is valid according to physics or is this due to a flaw in my simulation.

I meediate responses are highly appriciated