Trial combustion: A test engine from Lotus Engineering used to develop a new, efficient engine design.
Lotus Engineering
An engine from Lotus and Continental Powertrain consumes 15 percent less fuel.
A research project in the UK has developed a gasoline engine that it claims can reduce fuel consumption by 15 percent without losing power.
The key to the new design is the way in which fuel and air are separately introduced into the engine cylinders. By experimenting with different regimes for directly injecting fuel while varying the opening and shutting the air inlet valves, the researchers say they have achieved the major breakthrough in performance--and developed a "concept-car engine" that is gaining interest from big auto makers.
The aim of the project, a collaboration between two leading car engine development companies, Lotus Engineering and Continental Powertrain, and two universities, Loughborough and University College London, is to reduce losses caused by the engine throttle. In conventional engines, the throttle is kept partially closed except during full acceleration, obstructing the flow of air and reducing the pressure and density of the air that enters the cylinder. This forces the engine to work harder to pull air into the cylinder. That wasted energy can be saved by controlling the mass of air that enters the cylinder not with the throttle, but by varying the timing of valve openings at each cylinder. This also enables engines to be made smaller and more efficient.
Such adjustments aren't possible with conventional variable-valve engines, which use mechanical controls that restrict their operation. But Lotus Engineering has developed a hydraulic system that it says enables "complete control" of the timing, duration, and lift of the valves. The researchers concluded that the best configuration of valves was four for each cylinder, two for air intake and two for exhaust. According to the company's principal engineer, Graham Pitcher, engine output could be controlled by closing one intake valve and slightly opening the other.
A hydraulic hybrid technology lets trucks burn a third less fuel than they normally would.
Free-piston engines could be used to generate electricity as efficiently as, and less expensively than, fuel cells.
Electromagnetic Valve Actuator
Why add complexity and waste energy with a hydraulic system?
A fully flexible electromagnetic valve actuator was recently recognized by the R&D Magazine (http://www.rdmag.com/) as one of the 2008 R&D 100 Award Winners. For details: http://www.engineeringmatters.com/indexproj.htm
It has been known for quite some time that if you provide complete mixing of fuel plus oxidant (i.e. homogeneous mixture) you can get efficient complete combustion. Modern steam engines and gas turbines do this routinely.
Instead of adding complexity simply attack the base problem. Premix the fuel and oxidant, gaining control not only of the ratios of the two constituents, but of the absolute quantity.
This approach will free the designer to consider the quantity of constituents question in more detail involving the cylinder compression ratio and various ignition strategies such as diesel operation and catalyticly initiated combustion.
Continuing to improve a flawed approach doesn't lead to better technology only a more expensive one.
Big advance? Not so obvious...
This is only natural evolution based on research work, another step. Everyone see the problem with electro-magnetic valves, if an electrical problem comes during normal use? Not nice to have an engine broken by a simple electrical problem ! Costs ? Why engineers don't explore more the mechanical solutions? I GIVE my R-VVA valvetrain system for development to a real interessted Company, this is the most simply variable valvetrain system, and permits continuous full variation in all parameters of valves work, elimination of throtle bodies, better intake and exhaust ducts design, increased power, larger torque power band, half-intake cycle for low and medium charges and rotational speed, etc. After we can make a very flexible engine according necessities, sure to have an more efficient and less polluting powertrain. The dream of all is to have an engine with the torque of a truck and at same time the power of an sport car? Or not?
Until today, the most advanced desmodromic variable valvetrain is from Pattakon-Greece, but the most simply variable valvetrain is my REVERSE-VVA system.
What I see is not the application of the best technologies, but by other side, the technologies who serves a few interests of some people.
In conclusion, I have seen this: the people involved around Automotive Industry development, only is focused in solving his own problems than they create; they not consider a broken with past and the implementation of completely new solutions and technologies.
Apart from general crisis, another problem in Automotive Industry is his own slow advance in innovations concerning Powertrain. This Industry has more than 10 years of retard, in technology.
Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
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jpm000001
8 Comments
mgp?
So does this 15% less fuel mean the engine would go from 30 mpg to 34.5 mpg? Doesn't sound too dramatic. But still, a tip of the hat to the researchers.
Let's forget about these gas engines --electric motor efficiency blows them out of the water -- and do more research into better batteries.
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Siphon
152 Comments
Re: mgp?
Agreed. A 15% reduction is not exactly 'sipping'. That would have to be more like 80-90% reduction. Oh wait, that's impossible!
Electric motors and batteries it is. Thermodynamics says so. Still, an efficient generator for a series hybrid or series plugin hybrid would be very useful, so any research, even incremental, is of help.
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