Fuel-Efficient Engine for Cheaper, Lighter Spacecraft

Fuel-Efficient Engine Image
The experimental rotating detonation engine enabled engineers to control different parameters such as the size of the gap between the cylinders. The feed lines (right) direct the propellant flow into the engine. On the inside, there is another cylinder concentric to the outside piece. Sensors sticking out of the top of the engine (left) measure pressure along the length of the cylinder. A camera would be on the left-hand side, looking from the back end of the engine. (James Koch/University of Washington)

Ending NASA’s Space Shuttle into orbit required more than 3.5 million pounds of fuel, which is about 15 times heavier than a blue whale. But a new type of engine — called a rotating detonation engine — promises to make rockets not only more fuel-efficient but also more lightweight and less complicated to construct. There’s just one problem: Right now, the engine is too unpredictable to be used in an actual rocket.

Researchers at the University of Washington have developed a mathematical model that describes how these engines work. With this information, engineers can, for the first time, develop tests to improve these engines and make them more stable.