The actuator disc theory for wind turbines including losses and non-uniform velocity distribution

Abstract

In a paper published in 1989 the actuator disc model proposed by Betz to represent the flow across a wind turbine has been set right by taking losses into account. In the present paper this model is improved by introducing global correction factors at the entry and the exit of the machine. The resulting extent of the actuator disc concept shows that management of the velocity field may lead to a satisfactory adjustment between the power output and the velocity deficit range. A significant shift in the characteristics of the machine, associated to a slight enlargement of the wake, is made possible in the frame of the new model. Comparison reveals a better fit with experimental data.