Application of engineering models to predict wake deflection due to a tilted wind turbine

It is a known fact that the power produced by
wind turbines operating inside an array decreases
due to the wake effects of the upstream turbines.
It has been proposed previously to use the yaw
mechanism as a potential means to steer the upstream
wake away from downstream turbines, however
such a mechanism introduces control complications
due to changing wind directions. Deflecting
the wake in the vertical direction using tilt, on the
other hand, overcomes this challenge. In this paper,
the feasibility of steering wake is explored in
a simple uniform inflow case. This is done by trying
to model the wake deflection as a function of
the yaw/tilt angle and the rotor thrust, initially using
the momentum and vortex theories. Thereafter,
a relatively more promising empirical model based
on a set of actuator disc CFD computations is proposed.
Finally, comments are made on the feasibility
of wake control using yaw/tilt.