China claims ‘world’s first’ kerosene-powered engine could propel jets nine times the speed of sound

Chinese researchers claim to have created the "world's first" hypersonic detonation wave engine, which can propel a plane at Mach 9, nine times the speed of sound, using inexpensive jet fuel.

The oblique detonation engine underwent a number of successful ground tests at Beijing's JF-12 hypersonic shock tunnel, the South China Morning Post (SCMP) reported on Friday.

"No test results for [hypersonic detonation engines using] aviation kerosene have been made public before," said the researchers.

The researchers released technical information on the kerosene-powered engine in a report published in the peer-reviewed Journal of Experiments in Fluid Mechanics on November 11. The tests were carried out earlier this year, noted SCMP.

The team experimenting with the engine, which generates thrust by a burst of explosions, was led by Liu Yunfeng, a senior engineer at the Institute of Mechanics, Chinese Academy of Sciences.

Aviation Kerosene-powered detonation engine

Compared to other hypersonic engines like the scramjet, a detonation engine can operate more effectively and with greater power.

A succession of explosions are set off by the detonation wave. These explosions occur almost rapidly and release a lot more energy than traditional combustion does with the same amount of fuel, especially at speeds beyond Mach 8.

Detonation engines have been developed by scientists all around the world; however, they typically use hydrogen fuel, which is expensive and explosive.

Jet fuel, known as RP-3, which is frequently found in Chinese airports, powers Yunfeng's engine.

Due to its high energy density and simplicity of storage and transportation, "Aviation kerosene is the fuel of choice for air-breathing engines," Yunfeng claimed.

Although the concept of using jet fuel to propel hypersonic flight has been around for years, "It is not easy to detonate," said Yunfeng.

Scientists have had problems because it is difficult to ignite the kerosene in hot, moving air.

According to computer simulations, an engine powered by kerosene would require a detonation chamber that was ten times longer than an engine powered by hydrogen.

The additional length would be impractical for the majority of hypersonic aircraft since each millimeter matters, as per the team.

The Chinese researchers, however, discovered that a straightforward modification—adding a thumbnail-sized bump to the engine's air inlet surface—could facilitate kerosene ignition while maintaining a compact chamber.

The goal

The DF-17 and YJ-21 are two hypersonic missiles that China has developed that can strike a structure or a vessel that is moving while avoiding the majority of air defense systems.

By developing a fleet of planes that can deliver passengers anywhere on the globe in only a few hours, the Chinese government hopes to discover uses for hypersonic technology in the civil sector.

Regular long-distance flights under challenging circumstances must be possible for hypersonic aircraft.

However, scientists and engineers working on the technology say that lowering construction and operating costs is still a significant problem.