New diagnostic, simulation technology offers insights into hypersonic flight

Aerospace engineering has always had a preoccupation with speed. Now researchers at the University of Cincinnati (UC) are pushing the boundaries of what’s possible, practical, reliable, and safe at 5x the speed of sound – more than 3,800mph.

“The bottom line for aerospace is to go farther, faster, with more payload. That’s the fundamental question for anything that flies,” says Prashant Khare, director of UC’s Hypersonics Lab and head of UC’s Department of Aerospace Engineering and Engineering Mechanics. “And we strive every day to come up with new technologies or science concepts that might lead to improvements.”

Hypersonics is getting increasing attention for military applications in the race to develop faster weapons – and perhaps one day aircraft – capable of evading deterrent technology.

“The challenge is not only how fast we can go, but do we have materials that will withstand the speeds we want to go?” according to Khare.

“Friction creates the heat. Can we come up with new materials or cooling technologies so we can go fast?” Khare asks. “The next question is how do we go that fast? That’s more related to traditional propulsion or combustion sciences.”

The Hypersonics Lab’s work at Digital Futures has examined how changing surface dynamics alters the fundamental physics of hypersonic flight systems. Engineers also are learning more about the bizarre physics observed at high speeds. Fluids behave weirdly at hypersonic speeds as molecules break apart and reform, creating a nonequilibrium state.

Collaboration with the Army Research Laboratory is leading to engine improvements to prevent stalling at such high speeds.

“Hypersonics is a multidisciplinary field of research that requires the insight of a passionate community intentionally pursuing the knowledge it has to go faster and higher,” says UC engineering student Jeremy Redding.

In his lab, Khare and his students use computer simulations to study the fundamentals of new propulsion systems for rotating detonation engines, which are more efficient than today’s jet engines, and supersonic combustion ramjet engines.

Engineers are deploying tools such as spectroscopy, Raman scattering, and photonic Doppler velocimetry to study hypersonics. Meanwhile, supercomputers allow Khare and his students to record hypersonic variables in fine detail in simulations. Capturing just one millisecond of hypersonic flight in simulation can require millions of computing hours.

“With advances in experimental diagnostics, technology and computing, we’re now at a point where we can understand it because we have these new tools,” Khare says.

With so much external interest in this topic from government agencies and aerospace companies, careers in hypersonic technology are promising.

“When people talk about something simple, they’ll often say, ‘It’s not rocket science,’” Khare adds. “But this is. This is rocket science.”

University of Cincinnati College of Engineering & Applied Science
https://ceas.uc.edu/