[duybk2501]

Hi everyone,

My name is Duy and I am a new Fluent user and don't have much experiences in this area. I post my question here, hopefully everyone can help me. I got a small trouble during simulating a flow past a circular cylinder in 2D. The problem is quite familiar and very basic one.

I simulate at Reynolds number of 180, in which the flow is in the wake transition regime, I used structured mesh (grid). The boundary conditions at sidewalls are symmetry, and cylinder is wall with no-slip. So, what is the most feasible turbulent model I can use for this problem? I did try with laminar model, and the values of CL and CD seem of to be good (CD =1.36, CD =0.63), but they are higher than the values of references (CD ~ 1.33 and CL ~0.60). I tried to get accuracy result by using a very fine mesh (Nc=480), but it didn't work, CL and CD were not reduced further . Then, I see a published paper using k-w SST model to simulate the problem at Re =100 and 200. So, there results are in agreement with references .

My questions:

1. Can we use turbulent model for laminar or laminar transition regime?
2. How can I get a better result if I choose laminar model?

Thank you for reading.