VAWT 2D Analysis Rotating Region problem

[cfdH3PHP]

Hello everyone I''m trying to simulate a VAWT (Darrieus type with three blades (Airfoil NACA 0018) in 2D). I did the design with Autodesk INVENTOR using surfaces. My control volume is a rectangle where the boundary conditions are velocity 12 m/s, pressure 0 atm and slip simmetry in the lateral walls. For the rotating movment of the rotor I used rotating region with the rpm fixed, so I can see in the rotating region results if the hydraulic torque is possitive, which i think means that wind has enough momentum to allow rotate the wind turbine at that rpm.

The problem is that at the moment that I run the simulation, the ring that i put like rotating region varies instantanially the velocity, like if the fluid inside the ring does not interact with the flow in the "stator" region (you can see it at the attached image).

I read a lot of information about rotating region looking in the official documentation, webinars and another post in the forum and i tred to correct all the things that could cause a problem in the simulation like make a finer mesh, put a lower time step, make that the turbine rotate less than 1 degree por time step (in this case 0,001 degree) and make a rump up of 50 time steps where the turbines reach steady rpm. However the problem in which the rotating region  act like if is isolate of the "stator" region" and looks like a solid persist. In the images below are attached how is the mesh.

The Vwind is 12 m/s and the wind turbine rotates at 10rpm. The solver settings are a time step of 0,00001667 which means the rotor turn 0,001 degrees per time step. The idea is make the rotor turn 5 times in the simulation so I put a total of 1.800.000 iterations (If that's crazy let me know please). I chose the turbulence model K-omega SST.

If anyone has some proporsals to improve the simulation and doesn't have this problem i'd be greatful, I also though that use the motion function instead of rotating region would give better results but increment a lot the calculation time.

Thank you.