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Swept Wind Turbine Blade Aeroelastic Modeling For Loads And Dynamic Behavior, Scott M. Larwood, Mike Zutek
Swept Wind Turbine Blade Aeroelastic Modeling For Loads And Dynamic Behavior, Scott M. Larwood, Mike Zutek
Scott M. Larwood
A dynamic modeling effort of a swept-blade wind turbine rotor has been conducted. The swept-blade concept was used for increased energy capture without an increase in the turbine loads. The work is part of a Department of Energy contract for increased wind energy capture at low-wind speed sites. The blade works by twisting to feather under aerodynamic loads at the outboard region. Conceptual design of the blade resulted in a 28 m blade radius for eventual testing on a normally 50 m diameter turbine. The blade was modeled with codes developed by the National Renewable Energy Laboratory. Comparisons were made …
Wind Turbine Rotor Fragments: Impact Probability And Setback Evaluation, Scott M. Larwood, C. P. Van Dam
Wind Turbine Rotor Fragments: Impact Probability And Setback Evaluation, Scott M. Larwood, C. P. Van Dam
Scott M. Larwood
With increasing installation of wind turbines, the exposure to the hazard of impact from blade fragments increases. Local authorities use setbacks to reduce the risk by limiting the distance from wind turbines to adjacent property lines and dwellings. Unduly conservative setbacks are a deterrent to wind energy development. To determine appropriate setbacks, the authors developed a fragment trajectory model based on fragment rotation and aerodynamics. The model was used to simulate fragment trajectories at various rotor speeds, with randomly generated inputs for wind speed, wind direction, rotor azimuth, and rotor break position. Four sizes of wind turbines were studied, with …
Design Studies Of Swept Wind Turbine Blades, Scott M. Larwood, C. P. Van Dam, Daniel Schow
Design Studies Of Swept Wind Turbine Blades, Scott M. Larwood, C. P. Van Dam, Daniel Schow
Scott M. Larwood
The growth of wind energy is sustained by innovation that lowers the cost of energy. One recent innovation is the swept blade, which deflects in operation and lowers loads. With sweep, a design rotor diameter can increase, capturing more power, with the loads remaining within limits. This concept has been demonstrated in a U.S. program and is in commercial production. This paper describes a parametric study of swept blade design parameters for a 750 kW machine. The amount of tip sweep had the largest effect on the energy production and blade loads; other parameters had less impact. The authors then …
Comparison Of Upwind And Downwind Operation Of The Nrel Phase Vi Experiment, Scott M. Larwood, R. Chow
Comparison Of Upwind And Downwind Operation Of The Nrel Phase Vi Experiment, Scott M. Larwood, R. Chow
Scott M. Larwood
Wind tunnel data are presented comparing upwind versus downwind operation of the National Renewable Energy Laboratory's Phase VI wind turbine. Power was not reduced as expected with downwind operation, which may be attributed to inboard three-dimensional effects. Average flap bending loads were reduced with downwind coning and compared well with prediction. Blade fatigue loads were increased with downwind operation; however, fatigue was mitigated with an aerodynamic tower shroud (fairing). The shroud needs to remain aligned with the freestream, demonstrated by an increase in fatigue loads from a 10° error in shroud alignment. Pressure data were acquired of the tower wake …