Advanced Opposed-piston Two-stroke Diesel Demonstrator

A U.S. Army RDECOM TARDEC Small Business Innovative Research (SBIR) program funded the exploration of an advanced technology opposed-piston, two-stroke diesel research engine as a potential alternative to four-stroke diesels and gas turbines for combat vehicle prime power. A liquid-cooled, opposed-piston, two-stroke diesel research engine was developed using an iterative process of analysis, design, fabrication and testing. The 3-liter displacement engine incorporated 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.

A series of three increasingly advanced engines were built and dyno tested. The fully instrumented engines accumulated over 100 hours of dyno operation. The ancillary systems - lubrication, cooling, and supercharger - were driven by variable speed electric motors. All engine systems and operations were electronically managed and programmable. A 1034-kPa BMEP engine was delivered to TACOM.