Submitted via IRC for AndyTheAbsurd
It's called Spark Controlled Compression Ignition, and Mazda made it work.
Despite rumors to the contrary, the internal combustion engine is far from dead. Recently we've seen several technological advances that will significantly boost the efficiency of gasoline-powered engines. One of these, first reported back in August 2017, is Mazda's breakthrough with compression ignition. On Tuesday, Mazda invited us to its R&D facility in California to learn more about this clever new Skyactiv-X engine, but more importantly we actually got to drive it on the road.
The idea behind Skyactiv-X is to be able to run the engine with as lean a fuel-air mixture (known as λ) as possible. Because very lean combustion is cooler than a stoichiometric reaction (where λ=1 and there is exactly enough air to completely burn each molecule of fuel but no more), less energy is wasted as heat. What's more, the exhaust gases contain fewer nasty nitrogen oxides, and the unused air gets put to work. It absorbs the combustion heat and then expands and pushes down on the piston. The result is a cleaner, more efficient, and more powerful engine. And Skyactiv-X uses a very lean mix: a λ up to 2.5.
(Score: 0) by Anonymous Coward on Wednesday January 31 2018, @01:39AM
Yeah, well, split hairs all you want, I consider ignition (rapid oxidation involving hot plasma) to be the tipping point in the context we are dealing with. And I was all inclusive. Chemicals are medieval. We need to learn more about amplifying and controlling mass attraction. It's much more appealing, and you won't get lost so easy if you're being pulled to your destination, instead of trying to push at just the right angle and force. Talk about putting the cart before the horse!