Dr. Norbert Mueller, an associate professor at Michigan State University’s (MSU) college of engineering, plans to have a new engine generating power through a 25-kilowatt battery out later this year. The new engine connected to a generator and buffered by a battery and likely some capacitor storage would be powerful enough to run a full size vehicle.
The new engine is a “disk wave” chamber instead of a piston in a cylinder. The disk wave principle uses a novel internal system to generate shock waves by igniting a compressed air and fuel mixture that propels rotors. No valve gear, pistons, connecting rods or crankshaft.
ARPA-E, the Advanced Research Projects Agency-Energy provided a $2.5 million ARPA-E grant in 2009 to Mueller who says, “The wave disk engine is smaller, lighter and easier to manufacture. You have to be aggressive with your research in today’s world if you want to get anywhere.”
Mueller’s engine designed is said to reduce the weight of the engine by 30%, cut the weight of vehicle by up to 20%, improve the fuel economy by using 60% of the fuel for propulsion, reduce the total cost by up to 30%, and reduce the CO2 emissions by 90%. That’s a very big list with big numbers all in the shadow of the American car companies’ headquarters in Detroit.
Mueller says they have four working bench prototypes, “We have engines – real, working, good-sized models – running right now.” The MSU research team will turn one of them into a 25-kilowatt disk wave engine and generator package this year, “We’ll be able to drive a full-sized hybrid vehicle, or even a hybrid SUV.”
The engine is a system of rotors with radial channels that work due to timing as the shock waves are generated and move through the system. To grasp what’s going on, consider a turbine with air going in one end and exhaust gas exiting the other, like a set of fans. The wave engine – it seems – is like a squirrel cage or centrifugal fan with the air coming in the center and exhaust leaving the perimeter. Seems simple . . . vent the incoming air fuel mix properly, ignite it and vent it out at the right moment.
Mueller said, “The engine was obviously hard to design. But it’s easy to manufacture. There are many parties – national and international – now interested in it, both in the automotive and base power sectors. Interest in the engine, that’s not a problem.”
The wave disk engine offers a major improvement using 60% of the fuel to create power, making it up to four times as efficient as today piston engines. That offers a whole new calculation on fuel use. It would also stuff a plug into the progress of grid charged electric vehicles. Consumers and the oil companies will love this – cutting 75% of the gas bill for one and staying in the game for the other is a natural symbiosis.
In case you’re wondering why the piston engine isn’t ever going to catch up to turbine types, it’s the working function problems. Pistons (plus the pins and a part of the mass of the connecting rod) have to go up and down essentially stopping and starting with the acceleration and deceleration twice with each crankshaft turn. Lots of energy gets used doing that. Plus there is the air turbulence inside the crankcase – twice the displacement of the engine gets pumped in every revolution using more energy. There are also all those moving parts, compressing springs and other things gong on. It’s astonishing the modern internal combustion engine is as efficient as it is.
Mueller can hold the bench prototype engine in just one hand. The engines would be relatively easy to manufacture and reduce the overall weight of a car by hundreds of pounds, enabling hybrid vehicles to be perhaps 20 percent lighter and 30 percent less expensive. A series hybrid could be very desirable, indeed.