Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Engineers Study How Hills, Nearby Turbines Affect Wind Energy Production

15.12.2011
Hui Hu pulled a model wind turbine from the top of an office filing cabinet.

The turbine tower was just 10 inches high. Its three blades were 10 inches in diameter. It was a perfect 1:320 scale reproduction of the 80-meter diameter wind turbines spinning across Iowa, the country’s second-ranked state in installed wind power capacity.

That mini turbine is helping a research team led by Hu, an Iowa State University associate professor of aerospace engineering, understand how hills, valleys and the placement of turbines affect the productivity of onshore wind farms.

While the wind industry has data about offshore turbine performance over flat water – especially from European studies – Hu said there’s little data about the effects of uneven ground on wind turbines.

And so Hu and his research team have created the mini turbines and started running tests in Iowa State’s $1.25 million Aerodynamic/Atmospheric Boundary Layer Wind and Gust Tunnel.

“We want to work with the wind turbine industry to transfer some of our findings,” Hu said. “We can help boost total energy capture. And we can lengthen the lifetimes of wind turbines, making them more efficient.”

The research team led by Hu includes Richard Wlezien, professor and Vance and Arlene Coffman Endowed Chair in Aerospace Engineering; Partha Sarkar, a professor of aerospace engineering, of civil, construction and environmental engineering, and director of Iowa State’s Wind Simulation and Testing Laboratory; Zifeng Yang, a former Iowa State post-doctoral researcher and now an assistant professor at Wright State University in Dayton, Ohio; Wei Tian, a post-doctoral research associate in aerospace engineering; and Ahmet Ozbay, a graduate student in aerospace engineering.

The engineers’ studies are supported by a three-year, $300,000 grant from the National Science Foundation and a two-year, $100,000 grant from the Iowa Alliance for Wind Innovation and Novel Development.

The researchers are using wind tunnel tests to quantify the characteristics of surface winds over hilly terrains, determine the best placement of wind turbines on hilly terrains and find the best design for large wind farms on hilly terrains.

Experiments include:

• Mini generators mounted inside the mini turbine nacelles measure power production

• Sensors mounted at the base of the mini turbines measure the wind loads placed on turbines and turbine towers

• Advanced flow measurements such as particle image velocimetry (which uses a laser and camera to take nearly simultaneous images that show the movement and velocity of individual particles) to measure wind flow fields, the wind vortices created by the tips of turbine blades and the total wind energy captured by the blades.

Hu said preliminary results indicate that wind turbines on hilly terrain are hit with much higher wind loads than turbines on flat terrain. The experiments also show that, compared with turbines on flat ground, wind flowing over hilly terrain recovers its power potential more rapidly as it moves from turbine to turbine.

Data from the wind tunnel indicate a turbine on flat ground in the wake of another turbine at a distance equal to six times the diameter of the turbines loses 13 percent of power production. A turbine in the wake of another with the same downstream distance on hilly ground loses 3 percent of power production.

“That means you can put wind turbines closer together in hilly terrain,” he said.

In November, Hu, Yang and Sarkar published the first paper about their wind-turbine studies – “Visualization of the tip vortices in a wind turbine wake” on the Journal of Visualization’s website. The three researchers also presented findings of their turbine wake studies at the June 2011 Applied Aerodynamics Conference of the American Institute of Aeronautics and Astronautics.

The project’s next steps include building a nine-turbine array in Iowa State’s big wind tunnel to study power production and wind flows through a mini wind farm.

Hu is confident that data from the experiments can be valuable as more and more wind farms are built across Iowa and the country.

“These studies are telling us things we didn’t know before,” Hu said. “And this will help optimize the design of wind turbine layouts with consideration of the terrain.”

Mike Krapfl | Newswise Science News
Further information:
http://www.iastate.edu

More articles from Power and Electrical Engineering:

nachricht Microhotplates for a smart gas sensor
22.02.2017 | Toyohashi University of Technology

nachricht Positrons as a new tool for lithium ion battery research: Holes in the electrode
22.02.2017 | Technische Universität München

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>