[Felipe06]

Hello for everyone in this forum:

Recently, I was modeling a VAWT (Vertical axis wind turbine) Daerrius H type in 2D and I had a problem with the converge of the solution. The problem was that never converging the solution. I used the K epsilon model; the mesh was triangular elements. But, the results of momentum coefficient are negative or values highest than one and if I use the equation for calculate the power coefficient

Cp = Cm * TSR

I will get values of power coefficient higher, and the power coefficient should not exceed the Betz limit established in 0,59


I did this simulation in steady state using a MRF (Multiple Reference Frames). The main idea is to use the convergent MRF results and simulate a transitory stage using the sliding mesh technique.



I attached the domain used and the graph with the results of the momentum coefficient. I did 12000 iterations, because in the forum many people said that, they did more iterations to get the result.



If someone can help me, I would appreciate it.