berserkdroid
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Two research groups are working to replacing spark plugs with lasers. My bet's with the Japanese (Group 1)GROUP 1Lasers set to replace spark plugs in car enginesBy Lewis PagePosted in Science, 21st April 2011 10:15 GMTSpark plugs in petrol engines are set to be replaced by laser ignition systems, following development of new manufacturing techniques by Japanese boffins.The new research is to be presented to the world at an optics conference in Baltimore next month by Takunori Taira of Japan's National Institutes of Natural Sciences and his colleagues. Taira and his team have been working with spark-plug firms and Toyota subsidiaries to address the problems facing ordinary petrol-engine ignition.At the moment, as any automotive fule kno, the fuel-air mixture in a petrol engine's cylinder is ignited by a plug which generates a spark between its electrodes using high-voltage electricity. The spark plug is the limiting factor on how "lean" - how low in fuel - the mixture can be: in order to ignite a leaner mixture the spark must be hotter, and past a certain point this destroys the electrodes.But designers would like to make leaner-running engines as this would improve fuel economy and cut down on emissions.Lasers would potentially offer hotter ignition, and they have other advantages too. The timing of ignition would be more precise than with sparkplugs - on the very brief timescales over which cylinder mixtures change, the exact point at which a plug will spark is quite unpredictable.“Timing – quick combustion – is very important," says Taira. "The more precise the timing, the more efficient the combustion and the better the fuel economy.”Ignition by photon beam would also offer the option of focusing the hot spot in the centre of the cylinder rather than generating it at the top. This would allow the "flame front" of the exploding mixture to spread out in all directions and act more efficiently.All in all, then, laser-ignition engines would be a boon. But the trouble thus far has been that the necessary laser machinery is large. It can't practically be deployed at the cylinder head, and there's no option to pipe the laser pulses in as they are of such frequency and energy as to destroy optical hardware.“In the past, lasers that could meet those requirements were limited to basic research because they were big, inefficient, and unstable,” Taira says.But not any more. The Japanese boffins have come up with a way of making small, high-power lasers out of ceramics. Their protoype unit is made from two yttrium-aluminum-gallium (YAG) segments, one doped with neodymium, the other with chromium. It is just 9mm in diameter and 11mm long, and by using bursts of pulses less than a nanosecond in duration it can ignite a volume of lean fuel-air mix at two points simultaneously - this develops power more quickly and efficiently than lighting at just one point.The ceramic laser material is thought to be easily tough enough to stand up to conditions in a running car engine. The tech ought to permit much more efficient, lower-emission petrol cars in years to come - perhaps swinging the pendulum back towards petrol and away from diesel engines, which in recent times have become the fuel-sipping low-emissions choice.As petrol is somewhat cheaper than diesel to buy, and petrol engines are somewhat cheaper to make, this could be very popular.Taira and his colleagues will present full details of their work at the 2011 Conference on Lasers and Electro-Optics in Baltimore on 2 May. ®Source: http://www.theregister.co.uk/2011/04/21/laser_sparkplugs/GROUP 2Cars to be started by lasers instead of spark plugsBy Richard Gray, Science Correspondent 9:00PM BST 11 Jul 2009Scientists at Liverpool University and engineers at car giants Ford have developed a new ignition system which uses focused beams of laser light to ignite the fuel.The researchers claim the technology is more reliable and efficient than current spark plug technology and will enable cars to start more easily in cold and damp conditions.It is understood that Ford, the world's fourth largest car manufacturer, hopes to put the laser ignition system into their top of the range vehicles within the next couple of years before making it more widely available.Dr Tom Shenton, a reader in engineering at Liverpool University who is leading the project, said: "We are running engines everyday in our laboratory with this system now and our ultimate objective is have it inside cars driven by consumers."Lasers can be focused and split into multiple beams to give multiple ignition points, which means it can give a far better chance of ignition."This can really improve the performance of the engine when it is cold, as this is the time when around 80 per cent of the exhaust emissions are produced and the engine is at is least efficient."The laser also produces more stable combustion so you need to put less fuel into the cylinder."In current engines spark plugs are positioned at the top or bottom of a cylinder and they can often fail to ignite fuel effectively if the petrol is not in the right position in the cylinder.In the new system the spark plug is replaced by a laser powered by the car battery which is sent along thin optical fibres into the engine's cylinders where lenses focus the beam into an intense pinprick of light.When fuel is injected into the engine, the laser is fired, producing enough heat to ignite the fuel and power the engine.The researchers claim that the laser, which will need to fire more than 50 times per second to produce 3000 RPM, will require less power than traditional spark plugs.Some of the laser can be reflected back from inside the cylinder to provide information for the car on the type of fuel being used and the level of ignition, allowing the car to adjust the quantities of air and fuel automatically to optimise the performance.This raises the prospect of mixed fuel cars which can run on a number of different biofuels while ensuring they still run efficiently.A spokesman for Ford said: "Ford, like all vehicle manufacturers, is obliged by European legislation to reduce emissions and our work in this area is led by Ford's UK R&D centre in Essex."This collaboration with the University of Liverpool is part of that effort, with Ford contributing in kind, with engineering time and equipment use, as well as financially."The project has now been awarded a £200,000 grant by the Carbon Trust to help develop the system further. Transport accounts for 25 per cent of carbon emissions and it is hoped new ignition systems can help to cut this level of pollution.Robert Trezona, Head of Research & Development at the Carbon Trust, said: "Laser ignition is attractive in a number of ways."It has a real potential to reduce greenhouse gas emissions in the future by improving the ignition and combustion of fuel, particularly in engines starting from cold, but it can also be used in mixed fuel engines such as biofuels."Source: http://www.telegraph.co.uk/motoring/news/5803066/Cars-to-be-started-by-lasers-instead-of-spark-plugs.html