Cummins/Tula dDSF (diesel Dynamic Skip Fire)
I have been watching this study for a while along with the Cummins ETREE project that replaced an ISB 6.7L with an ISB 4.5L hooked up to a 130kW generator pushing a 175kW motor that netted over 60% be...
Forum Discussion
RoyJ....ditto...that chart is almost exactly what PWM looks like from experience in Industrial Motor Controls
Add that today's computer systems & injector systems are fast enough to keep the combustion chamber at the diesel stoichiometric air-fuel ratio 14.5:1 and even leaner in other parts of the CC
Am guessing so much leaner to get as complete a burn as can...that NoX might become an even higher issue(s)
Add that today's computer systems & injector systems are fast enough to keep the combustion chamber at the diesel stoichiometric air-fuel ratio 14.5:1 and even leaner in other parts of the CC
Am guessing so much leaner to get as complete a burn as can...that NoX might become an even higher issue(s)
RoyJ wrote:
Both real exciting technologies in the diesel front. The Skip Fire is almost like PWM for electric motors, and may be the big step we're waiting for in in-cylinder emissions control vs relying solely on after-treatment. Hopefully 1 day we can look back at the past 15 years as a "interim" emissions phase, much like gas engines of the 70s and 80s.
I've been saying for years we should look at series hybrids used on trains (GE's AC-AC drives can hit 90+% efficiency). It's much easier to optimize your prime mover for a few set-points, than a 3-D map of rpm vs throttle position.
With a battery, we can't use pure AC-AC of course. But a battery is also necessary because unlike a locomotive, we need more than 8 throttle settings, and also need instant response. The extra reserve capacity of the battery should make up for the rectification / inversion losses of AC-DC-AC.
