http://www.cat.com/cda/layout?m=37508&x=7
>From reading the caterpillar website more, it actually appears that their natural gas engines are spark ignition, not compression ignition. They use the same block and such as the diesel engine, but different heads and fuel system apparently. It also mentions different compression ratio options depending on the quality of the fuel. On 9/26/05, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > Typically they injected a small amount of the usual liquid diesel fuel, > say 5% of the total, which functioned as an igniter to start the natural > gas burning, much like a spark plug. The natural gas was mixed with the > intake air. > > They were called "dual-fuel" or "oil-field" engines, because they could > operate on whichever fuel was cheapest at the time, and both oil and > natural gas were readily available in the oil fields. > > I recall reading that natural gas has a detonation (knock) resistance > equivalent to 130 grade gasoline (a BMEP 30% above 100 octane's maximum) > and I expect that at lean mixtures it could take still higher compression > ratios. I believe that the compression ratios of the large industrial > diesels tend not to be great, maybe 14 or 16 to 1. With a big cylinder > the air loses less heat to the walls. I suspect the oil field engines > were/are unsupercharged. > > Doug Woodard > St. Catharines, Ontario, Canada > > > On Mon, 26 Sep 2005, Zeke Yewdall wrote: > > > alot of the > > industrial diesels for power generation are designed to run on natural > > gas instead of diesel, because of lower emissions and cost. I'm not > > sure what they do to the injection system to run a gaseous fuel in a > > diesel engine. > > _______________________________________________ > Biofuel mailing list > Biofuel@sustainablelists.org > http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): > http://www.mail-archive.com/biofuel@sustainablelists.org/ > > _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
