Results 271 to 280 of about 372,321 (309)

Ideal wind turbine performance at very low tip speed ratio

Journal of Renewable and Sustainable Energy, 2014
At very low tip speed ratios, wind turbine rotors behave similarly to stationary wings for which the well-known lifting line analysis gives the optimal loading. Lifting line analysis is applied to a stationary rotor of N blades for N = 1, 2, and 4.
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Fuzzy logic based optimal tip speed ratio MPPT controller for grid connected WECS

Materials Today: Proceedings, 2021
Abstract This paper proposes a fuzzy logic based optimal tip speed ratio controlled maximum power point tracking for grid connected variable speed wind energy conversion system. The general system includes a three bladed fixed pitch turbine, permanent magnet synchronous generator (PMSG), three phase uncontrolled rectifier, DC boost chopper, PWM ...
P. Sathish Babu, C.K. Sundarabalan, C. Balasundar, T. Santhana Krishnan   +3 more
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Effects of tip speed ratio on wind turbine wake meandering

Journal of Fluid Mechanics
This study utilises large-eddy simulation with the actuator line model to examine the effects of the tip speed ratio (TSR) on the wake-meandering characteristics of a wind turbine in uniform and turbulent inflows. It is shown that as the TSR grows, the onset position of the wake meandering moves closer to the rotor, and the magnitude of wake ...
Yan Wang, Guihua Zhao, Guoliang Liu, Yongze Zhou, Mingwei Ge, Zhen Ouyang, Zijing Ding, Ruifeng Hu   +7 more
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Experimental and Numerical Studies of a High Solidity, Low Tip Speed Ratio DAWT

48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, 2010
A numerical and experimental investigation of a Diffuser Augmented Wind Turbine (DAWT) has been conducted. Historically, the advantages of DAWT concept have been negated by higher material cost and less than stellar real world performance. The current configuration combines a duct augmentation concept with an optimized, high solidity, twisted flat ...
Michael Moeller, Kenneth Visser
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Assessment of optimum tip speed ratio in wind turbines using artificial neural networks

Energy, 2006
Wind turbine blade design depends on several factors, such as turbine profile used, blade number, power factor, and tip speed ratio. The key to designing a wind turbine is to assess the optimal tip speed ratio (TSR). This will directly affect the power generated and, in turn, the effectiveness of the investment made.
Ata, R., Yurdusev, M. A., Cetin, N. S.
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An Actuator Disc Theory for the Shed Wake at Low Tip Speed Ratios

SAE Technical Paper Series, 1965
<div class="htmlview paragraph">A model of flow through a helicopter rotor, suitable for estimating effects of shed wake in hovering and at low tip speed ratios, is described. With this method, the result for aerodynamic damping of blade bending oscillations is in agreement with more elaborate theories.
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Air-speed/Wing-tip Speed Ratios of Insect Flight

Nature, 1950
I HAVE made measurements of the wing movements of the tsetse-fly Glossina palpalis R-D. and other Glossina species in free flight, using a stroboscope and a large series of ‘Arditron’ flash photographs (duration about 1–2 microseconds). The wing-beat frequency for G. palpalis is 120 cycles per second; but investigation shows that the relative speeds of
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Performance and Loads of Variable Tip Speed Rotorcraft at High Advance Ratios

2015
This dissertation presents a lifting-line, comprehensive approach to predicting the performance and loads of high advance ratio rotorcraft. At high advance ratios, the reverse flow region is large and its unique aerodynamics impacts the rotor performance and dynamics more than at conventional airspeeds where they are often ignored.
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Tip Speed Ratio Influences on Rotationally Augmented Boundary Layer Topology and Aerodynamic Force Generation

Journal of Solar Energy Engineering, 2004
Under zero yaw conditions, rotational effects substantially and routinely augment HAWT blade aerodynamic response. To better comprehend the fluid dynamic mechanisms underlying this phenomenon, time dependent blade surface pressure data were acquired from the National Renewable Energy Laboratory (NREL) Unsteady Aerodynamics Experiment (UAE), a full ...
Scott Schreck, Michael Robinson
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Optimization of a Vertical Axis Micro Wind Turbine for Low Tip Speed Ratio Operation

10th International Energy Conversion Engineering Conference, 2012
This paper describes progress on a vertical axis wind turbine (VAWT) testbed aimed at the needs of a single family. VAWTs are potentially better suited than the more common horizontal axis wind turbine (HAWT) to meet the energy needs of homes and villages because of lower blade speeds and more benign failure modes; however, they are also more complex ...
Akshay Pendharkar, Ryan McGowan, Kevin Morillas, Mark Pinder, Narayanan Komerath   +4 more
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