In what could, semi-punningly, be described as a slow burn, investigators at the University of Central Florida have demonstrated a groundbreaking new “impossible” rocket propulsion system researchers have been unsuccessfully exploring since the 1960s.
It is believed that the system — referred to as a rotating detonation rocket engine — will allow upper stage rockets to be able to travel farther and burn more cleanly.
“The rocket propulsion system is based on detonations — controlled violent explosions on the order of exploding stars — that offer significant improvements, including higher performance and thrust, lower cost, and smaller sized engines,” Kareem Ahmed, an assistant professor in UCF’s Department of Mechanical and Aerospace Engineering who led the research, told Digital Trends. “It is difficult because the operation of the engine is based on harnessing these controlled explosions that travel ultrafast at Mach 5 and above.”
In the new rocket system, the rotating Mach 5 explosion detonations are continuous, sustained by feeding in hydrogen and oxygen propellants in exactly the right quantities. Getting the quantities wrong would result in the fuel slowly burning, rather than detonating. This is the challenge that has previously faced researchers, who struggled to find the right way to mix the necessary chemical propellants.
Get it all right, though, and the results are impressive. Mach 5 explosions create bursts of energy that travel at upward of five times the speed of sound. The detonations are contained in an engine body made of copper and brass. The system means that more power is generated while using less fuel than regular rockets. This means lightening the rocket’s overall load, which can also reduce costs.
So far, the research has remained strictly ground-based, performed at UCF’s Propulsion and Energy Research Laboratory. The work has been supported by funding from the U.S. Air Force Office of Scientific Research. But don’t expect it to stay Earthbound forever — although it may still be a while before a completed rocket with this propulsion system makes it to the stars.
“We are going through a strategic path forward for technological development,” Ahmed said. “The U.S. Air Force is targeting … a rocket launch flight test by 2025, which we are contributing to.”
A paper describing the work was recently published in the journal Combustion and Flame.