Читать книгу Wind Energy Handbook - Michael Barton Graham - Страница 53

The force on the air becomes, from Eq. (3.4),

(3.9)

As this force is concentrated at the actuator disc, the rate of work done by the force is TU_D and hence the power extraction from the air is given by

(3.10)

A power coefficient is then defined as

(3.11)

where the denominator represents the power available in the air, in the absence of the actuator disc.Therefore,

(3.12)