Analysis of inboard flow around the wind turbine blades

• Autorzy: Dumitrescu, H. , Cardos, V.
• Języki publikacji: EN

Abstrakty

EN

The complex flow in the rotor root area is analyzed by means of the boundary layer approach. The approach involves a radial angular velocity (Ekman) boundary-layer on the rotor disk rotating with an angular velocity smaller than that of the fluid, and the circumferential velocity boundary-layer developing on blades. The first explains the smaller adverse pressure gradient at the leading-edge of blades by a vortex-induced sucking effect, and the other shows the contribution of Coriolis force to the closed separation behavior on the suction side of the inboard blade sections, that explains the stall-delay phenomenon. Three-dimensional incompressible steady momentum integral boundary layer equations are used to analyze the leading-edge separation bubble on a rotating blade, including the effect of enhanced rotation at strong winds. The stall-delay phenomenon is described as a three contribution process: vortex-induced sucking effect by an Ekman layer type boundary-layer followed by Coriolis force, which acts in the chordwise direction as a favorable pressure gradient, and centrifugal forces producing a spanwise pumping effect. It appears that the first two contributions play the primary role for the rise of the inboard stall-delay and the centrifugal pumping effect is much less important than generally was supposed before.

Słowa kluczowe

PL

warstwa graniczna; turbina wiatrowa

EN

stall delay; three-dimensional boundary layer; wind turbines

• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2011
• Tom: Vol. 16, no 2
• Strony: 345-358
• Opis fizyczny: Bibliogr. 18 poz., wykr.

Twórcy

autor

Dumitrescu, H.

autor

Cardos, V.

• "Gh. Mihoc-C. Iacob" Institute of Mathematical Statistics and Applied Mathematics of the Romanian Academy P.O. Box 1-24, RO-70700, Bucharest, ROMANIA,

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