Printer Friendly

Blade control.

The Largest wind turbines can be so imposing that it might seem they are impervious to damage. But the Long blades are subject to vibrations that can degrade the material or even make them fail. To combat this, wind turbines have been engineered to shed power in high-wind situations, sometimes feathering the blades to reduce the lift on them.

Miki Amitay, a professor of mechanical engineering at Rensselaer Polytechnic Institute in Troy, N.Y., believes there is another approach. Amitay envisions wind turbine blades that, instead of trying to duck out of the wind, actively work to reduce the vibrations created by turbulent air flowing over their surfaces.

[ILLUSTRATION OMITTED]

To do this, Amitay and his colleagues are developing a system that would be embedded in the blades of a wind turbine and would change the aerodynamic characteristics of the blade on the fly. Sensors along the blade would monitor vibrations; when the blades started to flap, puffs of air would be shot out from jets along the Length of the blade to change the flow of air. By disrupting the natural air flow, the jets can break up vortices in the air that can form on the blade. This will reduce the stresses on the blade and increase the time between failures, all with an eye toward making Large turbines more cost efficient.

In preliminary studies, Amitay and his colleagues found that in a wind tunnel, blades had their vibrations reduced by a factor of 100 when jets of air were puffed across them.

The jets can also improve the ability of wind turbines to work in relatively light winds by maintaining a flow of air on the blades and thereby reducing the Likelihood of stalling. This may make it possible for Large wind turbines to harvest energy from even low-speed winds.

The New York State Energy Research and Development Authority recently awarded Amitay a $250,000 grant to develop this technology. As part of the research project, Amitay and his students at RPI will study the flow of air around turbine blades and how the airflow interacts with the blade. They will use that data to optimize blade design.

This section was edited by Associate Editor Jeffrey Winters.

COPYRIGHT 2011 American Society of Mechanical Engineers
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2011 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:TECH FOCUS: Instrumentation & Control
Author:Winters, Jeffrey
Publication:Mechanical Engineering-CIME
Geographic Code:1USA
Date:Jun 1, 2011
Words:370
Previous Article:Touchscreen Alternative.
Next Article:Only as strong as the weakest link: as the effects of the Sendai earthquake and tsunami ripple through the global economy, companies should shore up...
Topics:

Terms of use | Privacy policy | Copyright © 2019 Farlex, Inc. | Feedback | For webmasters