HCCI ENGINE DEVELOPMENT ACCELERATES The advent of more sophisticated electronic controllers is spurring renewed research and development into homogenous-charge compression-ignition (HCCI) engines, reports The Wall Street Journal. It notes that DaimlerChrysler, Ford, General Motors, Honda, Nissan, Toyota and Volkswagen all are working on the technology. An HCCI engine works similarly to a diesel powerplant: An air-fuel mixture is compressed until it heats enough to ignite. For gasoline engines, this combines the onethird greater fuel efficiency of a diesel system without the higher emissions of oxides of nitrogen and particulates associated with diesels. Automakers have been experimenting with HCCI technology for about three decades. But until now theyve been stymied by technical challenges such as controlling the combustion process at lower and upper engine speeds, something that is easier to do with high-powered electronic engine controllers. GM has developed an experimental engine that can operate in HCCI mode for about two-thirds of a typical engines operating rangeincluding smooth low-speed idling. During cold starts and at heavy loads, though, the powerplant uses sparkplugs to smooth out the combustion process. The automaker estimates the combination would be onefourth more efficient than a conventional spark-ignition engine. Automakers also are developing gasoline direct-injection systems, which the Journal describes as a precursor to HCCI engines. With direct-injection systems, air and gasoline are injected separately into the combustion chamber instead of being mixed together beforehand. Honda began using the technology last year in its Japanese model Stream car, and Volkswagen is offering a gasoline direct-injection engine in its new Audi A6. Using HCCI and other advanced technologies would enable automakers to more than double the 20% thermal efficiency of current internal combustion engines. Honda, for one, estimates that an HCCI Accord converting 40%-50% of gasolines energy directly to power could get 50 mpgdouble that of current Accords. And a gasoline-electric HCCI Accord could boost mileage to 70 mpg. Declares Honda CEO Takeo Fukui, The possibilities for improvement are almost infinite.
Christopher McCann, Squier Park, Kansas City, Missouri -1987 300TD, 150K miles, "Rotkäppchen" (Little Red Riding Hood) -1985 300SD, 209K miles, "Wulf" (http://www.pictureblogger.com/My-1985-Mercedes-Benz-300SD) -1976 240D, ManyK miles, "AKP-Wagen" (Alternativen Kraftstoffs Prüfenlastwagen = Alternative Fuel Test Vehicle) running WVO/WMO/LO/CO/WATF/WGL/WBF/DA/MS/lard/gas/kero/D2 mix (do not attempt this unless you are willing to sacrifice your IP, injectors, pre-chambers, etc.) -1971 Case 222 Hydrive, 12HP Kohler, 38" deck, Snowcaster, "One Banger" __________________________________ Yahoo! FareChase: Search multiple travel sites in one click. http://farechase.yahoo.com
