Flow Past circular cylinder no vortex

Hi folks,
I am using the same code posted on the site, (flow past circular cylinder). I have simulated the result for Re=20,40 but I am getting no vortex formation in the rear part of the cylinder, I dunno why…
xDim = 600
yDim= 250
obst X=xDim/5
obstY=yDim/2
obstR=yDim/10+1
tMax=10,000
Re=50.d0
Kindly let me know why I am not getting the vortices. The code is D2Q9. omega was 1.7 for this case approximately. The code is the same f90 code posted on the side for flow past cylinder. Kindly let me know error in the input data.
Regards
Prateek

Hello,

maybe the cylinder is located in the middle of the channel? Shift it by a few lattice nodes perpendicular to the flow direction. I also believe that a Reynolds number of 40 may be too small.

Timm

Hello,
Check this link out here Re=40 http://books.google.co.in/books?id=nk0SLXCZetQC&pg=PA55&lpg=PA55&dq=LBM+flow+past+cylinder+Sukop&source=bl&ots=HFB9bVGJWS&sig=8k2zrnB3_SptHCBVPwvbhWwPhms&hl=en&ei=Vm0jTITPEI_BcbzxkZ0F&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBQQ6AEwAA#v=onepage&q&f=false
This is Michael Sukops Book where he has compared the results of LBM with an experimental, at Re=40 the vortex starts to form…No such phenomenon is observed in my case…I am using the same code given on site…Have you used the code? I will try to displace the cylinder by few lattice nodes.
Regards
Prateek