Wrong results for Cl and Cd (straight line)
 

Hi,

I have try to run a simulation for the water flows through a 2D circular body. There are still straight line for Cl and Cd even though I have run the simulation which duration is 140 secs.

The values which I used in the Setup are shown as follows:
1) Re=1000 (turbulent flow) where density =1000, viscosity= 0.001, diameter of the circle =1m and velocity of the flow is 0.001m/s.

2) The scheme used is PISO (Skewness correction and Neighbor correction both are 1), turbulent model used is realizable k-epsilon (standard near-wall treatment), turbulent intensity is 6.747% and turbulence length is 0.07m (both are calculated from formula ontained from a paper)

3) Backflow values all were set to be 0 at pressure outlet and absolute criteria is 1e-6

4) Time step is 1400, time step size is 0.1s and iteration is 10.

I am wondering where the mistakes come out. Thanks for the kindly reply and help.

Regards,
Kit :)

Help please. Thanks a lot~