hot fire demo
NASA hot fire demo of full-scale rotating detonation engine hardware manufactured from small-scale design.
Courtesy NASA

Michaela Hemming, a doctoral candidate in the Department of Mechanical and Aerospace Engineering at The University of Alabama in Huntsville (UAH), is using a NASA Space Technology Graduate Research Opportunities (NSTGRO) fellowship to make advances in propulsion under the guidance of NASA engineers.

Hemming has designed a small-scale rotating detonation engine (RDE) manufactured by NASA as part of a joint research effort. The innovative engine burns fuel rapidly through a supersonic detonation wave – essentially a series of controlled explosions – that enable the device to deliver high performance in a relatively small volume. This innovative technology promises to enhance the range, speed and affordability of these engines when compared to traditional rockets, ramjets or gas-turbines.

Michael Mercier | UAH

“This is a four-year fellowship that includes a Visiting Technology Experience where I assist with research at NASA Marshall that aligns with my research,” Hemming says. “RDEs have demonstrated more power output and comparable performances to traditional deflagration liquid rocket engines, with lower fuel consumption and substantially lower complexity and size,” Hemming explains. “These devices are being considered especially for human landers and interplanetary travel to the Moon and Mars.”

Hemming is an aerospace systems engineering doctoral candidate performing her dissertation work with advisor Dr. Gabe Xu, associate professor of mechanical and aerospace engineering at UAH, a part of The University of Alabama System, who helped design the project. The UAH engine development team includes Dr. John Bennewitz, an assistant professor of mechanical and aerospace engineering, as well as graduate researchers Garrett Cobb and Ruthie Hill, and undergraduate researcher Jared Sauer. Hemming’s NASA advisor is Tom Teasley, a liquid propulsion systems development and test engineer at Marshall Space Flight Center (MSFC) in Huntsville, AL.

One of the specific goals of the grant has been to develop a modular subscale research test article to investigate detonation cycle rocket engine performances.

Courtesy Michaela Hemming

“The Combustion Devices Group at NASA MSFC are building a large-scale version of the engine I designed for UAH to understand the scalability of these engines,” Hemming says. “I am hoping to assist with that work late this summer term.”

The subscale engine was designed to be produced through additive manufacturing, or metal 3D printing, which uses a heat source – most commonly a laser – to fuse atomized powder particles together one layer at a time until the particular part is completed.

“Collaborating with NASA has been an incredible learning experience!” the doctoral candidate says. “Everything that we test and design at UAH has a direct impact on the research and decision-making of testing going on at MSFC. It has been very useful for us to have an immediate contact at NASA to ask questions, but what we work on at UAH informs their work just as much as their work informs ours. It is a true collaboration that complements both research institutions’ strengths.”

Hemming’s project will help inform the design of NASA's first full-scale 10,000 lbf rotating detonation rocket engine funded by NASA’s Space Technology Mission Directorate. Investment in these novel technologies and student engineers paves the way for a strong and sustainable space economy and helps to shape their future career paths.

“I hope to work on the research community’s toughest propulsion problems in space travel,” Hemming says. “I chose to come to UAH and the Propulsion Research Center for my graduate degrees because of this university’s reputation in experimental propulsion research. Not only would I get a quality education and research experience, but I would also be doing so under the advisement of professors who cared about my future as much as I did.”