Hi all I plotted the xy plot for Cp for a 2d cylinder at a low reynolds number of 500 with laminar flow model .the plot of Cp is not coming symmetrical for both the upper and lower surfaces while it should come exactly symmetrical .Please explain this anamoly in my plot?

Check if your model and mesh is symmetric...

Follow this example from Fluent if this helps...

http://flowlab.fluent.com/exercise/pdfs/cylinder.pdf

Hi AJ

thanks for the reply

I checked the link but the graph of Cp given in this also shows anamolous result as you may check the graph is not symmetrical for upper and lower surfaces of cylinder which it should be.

as far as I know.

above Re=40 there will be a vortex shedding behind the cylinder and this can cause the flow to be assymetric.

yes i agree with you but even if theres vortex shedding then it should show its effect in the Cp contours which i am not getting . Moreover dont you think that the shedding should still result in symmetry because of the symmetrical geometry . I am not sure about the results therefore need more light on the topic.