We’ve seen a number of innovations focused on improving the efficiency of hybrid cars. But while most of these new ideas have focused on optimizing battery capacity, here is one new piece of technology that is about to revolutionize the engine itself. Straight from the engineers at Michigan State University, this new ‘wave disk engine’ is 3.5 times more fuel efficient than a conventional combustion engine, can be run on almost any fuel and emits 95% less carbon dioxide.
Wave disk engines are built to be small, light, clean, simple, and cheap. The engine basically uses a disk that spins around super fast, and the disk is affixed with a number of channels that fill up with air and fuel as the rotor spins. Pressure builds up as inlets are blocked off, causing a shock wave within the chamber that ignites the compressed air and fuel. Essentially, as shock waves from the rotation compress and ignite fuel in the channels, the combustion causes the rotor to spin, generating electricity.
According to Michigan State University, the wave disk engine is about 20% lighter than a conventional engine and significantly cheaper to manufacture – a $500 OEM price for a wave disk generator that could power a car. But like all turbine-type engines, the wave disk engine is probably only able to provide high levels of efficiency when it’s at its optimal speed, meaning that it will likely be most useful to apply the technology to charge the batteries of an electric vehicle, rather than to drive the car alone.
Michigan State’s engineers have a prototype wave disk generator in action, and they hope to have a car-sized 25 kilowatt version running by the end of the year. They have also received a sizable $2.5 million from the Department of Energy for their project.
Via Dvice
@webley
You are correct that the 2nd law limits a perfect reversible Carnot cycle to around 73% but some turbine types come very close to this in the 65% range in lab settings. The reason they can do this is they convert the heat to work so quickly it does not have time to transfer into the surrounding material and since they are trying to cause detonation as opposed to straight combustion they can do this at very high pressures. As a side note most steel and aluminum engines have a theoretical limit of around 37% efficiency with most running below 17% and the most efficient right now sit in the 18%-20% range. Yes saying they can get 3.5 times more efficient is perhaps using the low range of efficiency and I too will be surprised if they beat 50% but 3.5*15 =52.5%. So while not convinced of that 3.5 number I would guess this could double real world efficiency which would still be great.
kllrbny
I dont care what RPM it operates at. If its a heat engine (and it is) then it is subject to the Second Law. Rather than making grandiose claims of efficiency, tell me the SECOND LAW efficiency.
klunk, cato, Webley and others:
You seem to misunderstand how this engine will work, as you all seem to be trying to compare this to a regular Internal Combustion Engine powering a car alone or in a parallel hybrid configuration.
This can be so efficient because it operates ONLY at the most efficient RPMs. Regular engines’ efficiency and CO2 emissions are based on their performance across the entire band of possible RPMs, but this only operates at a single RPM, which is the most efficient one, which is why both high fuel efficiency and low emissions can be accomplished. This is the whole premise of Series hybrid systems.
As well, higher RPMs are not necessarily more inefficient, it depends entirely on the design of the engine. They will pick the operating RPM to be the most efficient, there’s no reason to think or do otherwise.
If the video ends with “copyright 2009″ and the professor was talking about a three year timeline for implementation, does this mean we’ll see these in production vehicles for the 2012 model year this fall?
I am forever amazed by the new, ground-breaking efficiency technologies we read about on these threads, but over the last five years, not one of them has entered my environment.
So what gives?
There is no information as to the probable rpm that this engine will spin at, all that is mentioned is that the engine spins at very high rpm. The rpm is important for two reasons (a) fuel consumption will increase at high rpm (b) centripetal forces will also increase placing considerable mechanical stresses on the disk.
This is delightful! The dramatic reductions in CO2 emissions and increases in efficiency can allow for adaptation to virtually any sized model with opportunity for size reduction especially in personal transport! Not to mention the ability to run on more readily renewed bio-fuels!
Way to go!
Meu detetor BS também piscou! Vídeo babaca… não vi nenhuma realidade prática nessa conversa fiada.
@Tony:
(1) The man in the video says, “I want to see you, in three years, driving this hybrid electric vehicle with this engine in here.”
(2) To me, “hope to have … running” means “it’s not running yet.” Setbacks always occur when scaling up a prototype.
Conveniently forgot about the 2nd Law. There is no way it can be 3.5 times as efficient as an existing engine. It is after all a heat engine so is limited by the 2nd law to probably less than 60% efficiency and I would be surprised if it even got close to 40%.
Wow, sounds almost as good as a modern injected 2-stroke. Which you could have now rather than in a few years time. The technology has been proven viable; a 1400cc 2-stroke producing 400hp and up to 80% less emissions. You could have that tomorrow.
@Klunk:
My BS detector is flashing too. Did you read the same article as me? They have a prototype and hopw to have a 25KW version running by the end of the year. Where did you get this 3 years/no working model stuff from?
Oops. DOE invested. It’s now dead tech b/c Oil owns DOE.
My BS detector is flashing. A 95% reduction in CO2 would require 20 times the fuel efficiency. Increasing fuel efficiency by 3.5 times would cut CO2 emission by only 71.4%. He says this could be commercially available in three years, and yet he doesn’t even have a working model to demonstrate. He blithely says it could run on hydrogen, but hydrogen has very different properties from gasoline and other fuels.
You have to love engineers. Can’t wait to see it out in the world. This is a great accomplishment.
It’s a mini turbine.
Sweet.
Jct: Bravo. What a wonderful breakthrough. It would be nice to read how it came about. But what a wonderful improvement in efficiency!