Validation of analytical body force model for actuator disc computations

A new analytical model for representing body forces in numerical actuator disc models of wind turbines is compared to results from a BEM model. The model assumes the rotor disc being subject to a constant circulation, modified for tip and root effects. The advantage of the model is that it does not depend on any detailed knowledge concerning the actual wind turbine being analysed, but only requires information of the thrust coefficient and tip speed ratio. The model is validated for different turbines operating under a wide range of operating conditions. The comparisons show generally an excellent agreement with the BEM model, with, however, some deviations of the tangential force in the root area and at small values of the thrust coefficient.