The next generation of combustion-engine efficiency will come from a technology you probably have never heard of called homogeneous charged compression ignition (HCCI). As described by John Pinson, group manager of Diesel Engine Research at General Motors Research and Development Center, HCCI combustion in many ways resembles a diesel engine.
HCCI combustion could add another 20% improvement in fuel efficiency, without the high costs of hybrid technology. That is why all the major auto manufacturers have research into HCCI engines. Many issues must still be sorted out to take HCCI engines out of the labs and onto the street. HCCI Puts Gas Under Pressure Like its diesel cousin, the HCCI engine doesnt use a spark plug to ignite the fuel in the cylinder; rather, it uses pressure. HCCI is different in that the combustion process doesnt produce a flamethe fuel burns cleanly and clearly in the cylinder. Without the flame, the combustion is more efficient and produces much cleaner exhaust gases. To achieve this nirvana of combustion, the engine needs more precise control over fuel quality, valve actuation (including, possibly, multiple open/close cycles per combustion cycle), and direct fuel injection. To close the loop, the engine controller needs to monitor the combustion process. That is one area of research, as the solutions range from precise pressure sensors for each cylinder (the optimal solution) to simple knock sensors (used in some engines today to detect detonation). The precise control algorithms for HCCI are still under intense development. Unfortunately, the various auto manufacturers are pursuing their research programs independently. In our industry, we see consortiums formed when a potentially disruptive technology (such as EUV) needs extensive research. If the HCCI research could be centralized, we might be able not only to get the efficiency of HCCI engines sooner but also to get it from a much broader range of manufacturers. As it is, the auto manufacturers view engine development as a potential competitive advantage and a potential licensing opportunity. This is clearly the way Toyota views its hybrid power-train technology, and the company is benefiting from sharply increased sales of its Prius line of hybrid cars in the United States and from licensing its technology. Although the U.S. Department of Energy has funded research into HCCI, a government-sponsored consortium like Sematech could more quickly spread the benefits to multiple manufacturers and achieve the maximum impact. Japanese manufacturers Toyota and Honda have a significant lead in hybrid technology, but there is a new opportunity to take the lead in HCCI development. And driving both technologies will be faster, more capable microprocessors. 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
