Blade pitch

About: Blade pitch is a research topic. Over the lifetime, 5321 publications have been published within this topic receiving 63134 citations.

Actuator for adjusting a rotor blade pitch angle

Abstract: Actuator for adjusting pitch angle of a rotor blade of a wind turbine rotatably mounted on a rotor hub, comprising a first drive element connectable with the rotor blade, a second drive element in meshing engagement with said first drive element, a lubricating device for lubricating the two drive elements and lubrication controller. A rotor with a rotor hub, on which at least one rotor blade is rotatably mounted, with actuator adjustable pitch angle. A wind turbine comprising such rotor and such actuator. Selective lubrication of zero teeth of the gear stage of the actuator considers the rotary position of the drive elements of the gear stage with respect to each other. The lubricating device includes a lubricant passage to selectively supply portion of first drive element and/or portion of second drive element meshing therewith depending on engagement position of drive elements or rotary position of rotor blade.

Effects of Rotation and Blade Incidence on Properties of Turbomachinery Rotor Wake

Abstract: An experimental investigation of the effects of the speed of rotation on a turbomachinery rotor blade wake was conducted using a fan rotor in incompressible flow. Measurements were made at two different rotational speeds (1753 and 1010 rpm) with the same blade incidence angle. The blade incidence angle was also varied to discern the effect of blade loading. A three-sensor hot-wire probe mounted in a stationary frame of reference was used for the measurements made at several radial and axial stations in the near- and far-wake regions. The three-dimensional mean velocity and turbulence profiles, the wake defect, wake decay rate, turbulence intensities, and turbulence stresses are appreciably altered when the speed of rotation and the blade loading are changed. The wake defect is reduced and the radial velocity increased when the rotation speed is increased.

Different Wings Flowfields Interaction on the Wing-Propeller Coupling

Abstract: A high-portability numerical technique based on the method of free wake analysis (FWA) is described that analyzes the interference between an aircraft propeller and a wing having different planforms and computes the influence of the wing aerodynamic field on the propeller performance. For an isolated propeller and wing, the models employed are based on the FWA and Prandtl theory, respectively. The performance of the propeller in the presence of the wing is related to the wing angle of attack and to the variation of wing circulation and the corresponding induced velocity at the propeller disk. A numerical model, previously and successfully used, was implemented to account for the effects of a wing on the wing- propeller coupling. To test the robustness of the method, the available experimental data obtained on a scale model of an isolated propeller are used. In a correlation study, the results, when wing and propeller are coupled, show the sensitivity of thrust, power, and efficiency to inflow conditions and blade pitch, as well as to the wing planform