SwRI launches HEDGE-III; high-efficiency gasoline engine consortium targets LEV III, best efficiency of 43%
|HEDGE-III will investigate solutions to the primary barriers to high efficiency in gasoline engines. Source: SwRI. Click to enlarge.|
Southwest Research Institute (SwRI) has launched its third cooperative research program aimed at developing a high-efficiency gasoline engine for the light-duty automotive and medium-duty engine markets. This four-year effort will expand on earlier efforts to improve gasoline engine technology for future emissions and fuel economy requirements. (Earlier post.)
The HEDGE-III (High-Efficiency Dilute Gasoline Engine) consortium incorporates new and more aggressive efficiency, performance and emissions goals that are in line with existing and potential future regulations and expectations.
The overall goal is to develop the most cost-effective solutions for future gasoline engine applications. In addition to focusing on high levels of exhaust gas recirculation (EGR) and supporting technologies such as high-energy ignition and advanced boosting systems to develop strategies for high efficiency, the consortium will examine topics outside of cooled EGR that contribute to high-efficiency engine operation as well as develop tools for developing high efficiency engines.
HEDGE-III will target the Low Emission Vehicle III (LEV III) standards and, for the first time, extensively investigate cold-start technologies and monitor particle mass/particle number (PM/PN) emissions on a regular basis.
Efficiency goals include a best brake thermal efficiency (BTE) point of 43% and part-load efficiency goals that target diesel-like fuel consumption, with the target of best in class cycle emissions. In addition, the consortium will impose transient performance targets to make sure the high-efficiency engines are capable of providing high customer satisfaction.
The consortium will continue the work done in HEDGE-II, which developed dedicated-EGR technology that achieved nearly 42% thermal efficiency from a 2-liter engine. This engine, using SwRI’s D-EGR technology (earlier post), achieved roughly the same fuel consumption as a 2-liter diesel, but with the potential for ultra-low emissions and high specific power that typically are associated with a gasoline engine.
HEDGE-III will continue investigating high-efficiency concepts of Low Pressure Loop (LPL) EGR and D-EGR while developing tools for improved flame modeling and improved knock prediction for high dilution gasoline engines. Work will also continue on advanced ignition and boosting systems.
However, it will begin to shift the emphasis of the program to a more general examination of high-efficiency technologies with less direct emphasis on cooled EGR and more on interactions with dilute and variable valve train technology, and extending EGR to gasoline direct-injection and alternative-fuel engines such as natural gas.
During HEDGE-II, we built a 2-liter prototype dedicated-EGR gasoline engine that is the most efficient multi-cylinder spark ignition engine I’ve seen. The port-fuel-injected engine achieved 207 grams/kilowatt-hour, which compares very favorably to a similarly sized US diesel engine in terms of fuel consumption. With a combination of its fuel injection system and stoichiometric combustion, it has potential for ultra-low hydrocarbon emissions with no particulates.—Dr. Terry Alger, assistant director in SwRI’s Engine, Emissions and Vehicle Research Division
HEDGE-III is a four-year, annual renewal cooperative research program with an annual fee of $125,000 for original equipment manufacturers and $70,000 for suppliers. The more than 25 consortium members represent a broad industry cross section, including light, heavy-duty and off-road engine manufacturers, component suppliers, and oil and fuel companies from Asia, Europe and the United States.
The advantage of consortium membership is that the impact of the yearly contribution is multiplied by the number of participants, providing substantially more pre-competitive research than would be possible with funding from a single client. In addition, SwRI’s internal research programs involving control algorithms, advanced ignition technology and innovative combustion concepts will be shared with consortium members. These efforts often form the basis for focused research under the consortium.
As an independent R&D laboratory, SwRI has extensive experience in managing consortia. Since 1991, the Clean Diesel consortium has conducted research in low-emission diesel engines and in ultra-clean homogeneous charge compression ignition technology.