Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Flying on Hydrogen: Georgia Tech Researchers Use Fuel Cells to Power Unmanned Aerial Vehicle

30.08.2006
Georgia Institute of Technology researchers have conducted successful test flights of a hydrogen-powered unmanned aircraft believed to be the largest to fly on a proton exchange membrane (PEM) fuel cell using compressed hydrogen.
The fuel-cell system that powers the 22-foot wingspan aircraft generates only 500 watts. “That raises a lot of eyebrows,” said Adam Broughton, a research engineer who is working on the project in Georgia Tech’s Aerospace Systems Design Laboratory (ASDL). “Five hundred watts is plenty of power for a light bulb, but not for the propulsion system of an aircraft this size.” In fact, 500 watts represents about 1/100th the power of a hybrid car like a Toyota Prius.

A collaboration between ASDL and the Georgia Tech Research Institute (GTRI), the project was spearheaded by David Parekh, GTRI’s deputy director and founder of Georgia Tech’s Center for Innovative Fuel Cell and Battery Technologies.

Parekh wanted to develop a vehicle that would both advance fuel cell technology and galvanize industry interest. While the automotive industry has made strides with fuel cells, apart from spacecraft, little has been done to leverage fuel cell technology for aerospace applications, he noted.

“A fuel cell aircraft is more compelling than just a lab demonstration or even a fuel cell system powering a house,” Parekh explained. “It’s also more demanding. With an airplane, you really push the limits for durability, robustness, power density and efficiency.”

In November, the researchers will present details of the project at the Society of Automotive Engineers’ Power System Conference in New Orleans.

Fuel cells, which create an electrical current when they convert hydrogen and oxygen into water, are attractive as energy sources because of their high energy density. Higher energy density translates into longer endurance.

Though fuel cells don’t produce enough power for the propulsion systems of commercial passenger aircraft, they could power smaller, slower vehicles like unmanned aerial vehicles (UAVs) and provide a low cost alternative to satellites. Such UAVs could also track hurricanes, patrol borders and conduct general reconnaissance.

Fuel cell powered UAVs have several advantages over conventional UAVs, noted Tom Bradley, a doctoral student in Georgia Tech’s School of Mechanical Engineering who developed the fuel cell propulsion system. For starters, fuel cells emit no pollution and unlike conventional UAVs, don’t require separate generators to produce electricity for operating electronic components. “Another plus, because fuel cells operate at near ambient temperatures, UAVs emit less of a heat signature and would be stealthier than conventionally powered UAVs,” he said.

Breaking new ground

A few other research groups have also demonstrated hydrogen-powered UAVs, but these aircraft were either very small or used liquid hydrogen. “Compressed hydrogen, which is what the automotive industry is using, is cheaper and easier to work with,” said Bradley, “so our research will be easier to commercialize.”

In contrast to the smaller UAVs, which had no landing gear and had to be hand launched, Georgia Tech’s demonstrator vehicle operates like a full-sized aircraft, requiring no auxiliary batteries or boosters for take-off.

While little information has been released about other hydrogen-powered UAVs, outreach is an important part of Georgia Tech’s project. “We are laying the groundwork in design development that others can use to develop hydrogen-powered aircraft,” explained Dimitri Mavris, ASDL director and Boeing Professor in Advanced Aerospace Systems Analysis in Georgia Tech’s School of Aerospace Engineering. “By documenting the technical challenges we’ve encountered – as well as our solutions – we provide a baseline for others to follow.”

The researchers hope to see many other aircraft take to the skies on power from fuel cells.

“As significant as it is, we are not merely developing a one-of-a-kind airplane,” added Parekh. “We’re working to define a systems engineering approach for fuel-cell powered flight. We’re seeking to blaze a trail that others can follow.”

In addition to their upcoming presentation at the Society of Automotive Engineers meeting, the researchers presented papers earlier this year at meetings held by the American Society of Mechanical Engineers and the American Institute of Aeronautics and Astronautics. The project is supported with internal funding from GTRI, along with grants from the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF).

Difficult design game

“Hydrogen power requires a drastically different approach to aircraft design compared to conventional planes powered by fossil fuels,” observed Blake Moffitt, a doctoral student in Georgia Tech’s School of Aerospace Engineering who designed much of the aircraft.

To construct the fuel cell power plant, researchers bought a commercial fuel cell stack and modified it extensively, adding systems for hydrogen delivery and refueling, thermal management and air management. They also built control systems, such as data acquisition so information could be transmitted during flight.

Among design challenges:

Slim performance margins. Researchers developed innovative computer tools to analyze performance, which enabled them to optimize the propulsion system and aircraft design.

Weight management. Creative methods were used to trim pounds, such as using carbon foam for the power plant’s radiator.

Reducing drag, which the team achieved via long, slender wings (spanning 22 feet), a streamlined fuselage, a rear-mounted propeller and an inverted V-shaped tail.

Miniaturization. The fuselage measured 45 inches in length with a maximum width of 9.75 inches and maximum height of 7.25 inches. Finding components small enough to fit in this space required some ingenuity, such as using a pump from a liquid-cooled computer and a hydrogen tank designed for a paintball gun.

In June, researchers tested the vehicle at the Atlanta Dragway in Commerce, Ga.
Hot, humid, windy weather made testing conditions less than ideal and reduced thrust. Yet researchers were able to conduct four flights, with the aircraft traveling between 2.5 and 3.7 meters above ground for up to a minute at a time.

“Especially important, the data generated during these flights validated our design methodologies,” said Moffitt. “The data also indicated the aircraft is capable of longer, higher performance flights.”

During the next few months, the team will continue to test and refine the aircraft, making it more reliable and robust. Ultimately, they plan to design and build an UAV capable of a trans-Atlantic flight – something that Parekh believes will be possible within the next five years.

John Toon | EurekAlert!
Further information:
http://www.gatech.edu
http://www.gtresearchnews.gatech.edu/newsrelease/fuel-cell-aircraft.htm

More articles from Power and Electrical Engineering:

nachricht Ultrathin device harvests electricity from human motion
24.07.2017 | Vanderbilt University

nachricht Stanford researchers develop a new type of soft, growing robot
21.07.2017 | Stanford University

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: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

Chances to treat childhood dementia

24.07.2017 | Health and Medicine

Improved Performance thanks to Reduced Weight

24.07.2017 | Automotive Engineering

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>