The gas-turbine engine, or jet engine, isn’t only found on jets, but in other applications as well. The US Navy doesn’t only use turbines for their fighter jets, but also as generators on their ships. As the Navy moves to all-electric propulsion, they still need some kind of electrical generator.
Turbines are well-suited for development because of their relatively simple design and scalability. Turbines are also fairly easy to maintain when compared to standard internal combustion engine designs.
Current turbine technology, though, is somewhat inefficient. The fuel / air mixture is compressed and combusted internally, the exhaust of which drives the compression forward, as well as generators, machinery, or simple thrust. Even at its best, some fuel is burned outside of the compression zone or even outside of the engine, wasted.
A technology under development for the last decade, the Rotating Detonation Engine [RDE], might be set to enter the final stages of testing, which could increase power and efficiency. The RDE’s advantage over a standard turbine, is that the fuel is combusted by the compression created by the previous detonation. This would simplify construction and eliminate some of the parts and weight in a turbine.
“RDEs offer the potential for high dollar savings by way of reduced fuel consumption in gas-turbin engines,” explains Dr. Kazhikathra Kailasanath, who heads National Research Laboratory’s Laboratories for Computational Physics and Fluid Dynamics, “however, there are several challenges that must be overcome before the benefits are realized.”
The US Navy, currently in possession of over 400 turbines on 129 vessels, burns about $2 billion each year on fuel. Technologies that can increase fuel efficiency will definitely call their attention. The US Navy is looking into developing Rotating Detonation Engines, which promise to increase generator output by 10% while saving 25% in fuel costs. This could translate to nearly $400 million in fuel savings every year.