[dynamic]

Hi,
I'm running transient analysis on a three bladed vertical axis wind turbine in 2d using fluent, the issue i'm having is that the moment coefficient is fluctuating between positive and negative values, See attached.

I also have attached plots of the mesh and a pressure contour which shows no large discontinuities.

Im using the transitional turbulence model with a "simple" scheme and second order upwind.

I have my reference values set up as follows
Depth = 1
Length = radius of turbine
Area = diameter of Turbine X length of blades.

If anyone could provide me with help it would be greatly appreciated, thanks in advance