Advanced Diesel Engine 42% Brake Thermal Efficiency Technology Demonstrators

Battlefield delivered fuel (jet and diesel) with required security, storage, transport, and dispensing equipment is estimated to cost $418/gallon [ 1 ], thus the need for very fuel efficient light weight engines for repower and future vehicles is critical. The U.S. Army RDECOM TARDEC Small Business Innovative Research (SBIR) Program funded Advanced Engines Development Corporation (AED) for the exploration, development and application of advanced diesel engine technologies and to incorporate these technologies into demonstrator engines, a 4-cylinder and V-8's. AED based these demonstrators on current production GM gasoline engine diesel conversions employing commercial-off-the-shelf (COTS) advanced diesel systems and engine components. Using an iterative process of analysis, design, fabrication, and dyno testing a 2.2/2.4 liter displacement and 6.5 liter engines incorporating the latest technology in: high pressure common-rail fuel injection; high combustion charge air density utilizing a supercharger and turbocharger in-series with inter- and after-cooling; and a highly turbulent combustion system were developed. A series of three increasingly advanced 2.2/2.4 liter diesel engines were built and dyno tested. All engine systems and operations were electronically managed and programmable. The performance goals of: 42% brake thermal efficiency, 18-25 bar BMEP; and specific heat rejection to coolant and oil of 16-21Btu/hp-min were met or exceeded in fully operational lightweight high power density engines. These developed advanced diesel technologies were incorporated into two V-8 series engines, one based on the 6.5L HMMWV engine and the other on GM LS high performance gasoline V-8's. These replacement engines could upgrade the HMMWV and other applications through the modernization/recapitalization programs to have a military fleet of high powered, very fuel efficient diesel engines.