ROCKLEDGE, FL – December 22nd, 2010 – Mainstream Engineering Corporation (MEC), a leading research and development company specializing in thermal control and energy conversion, has been awarded a contract from the U.S. Marine Corps to develop controls for premixed-charge compression-ignition (PCCI) engines using real-time combustion feedback.
The Defense Science Board Task Force on DoD Energy Strategy recently concluded that battlefield fuel consumption is unnecessarily high, which compromises operational capability, increases support costs, and exposes support operations to more risk than necessary. Existing military engine designs have focused on ruggedness and reliability rather than fuel efficiency. Military diesel engines used for power generation and vehicle prime power have lagged behind modern automotive diesels in technology and performance.
In developing the next generation of military diesel engines, attention must be given to fuel efficiency, noise, and emissions. To address this challenge, MEC is developing a pressure-feedback controller that will allow existing military diesel engines to operate in a PCCI mode. PCCI combustion has received a great deal of recent attention by the engine research community for its potential for very low exhaust emissions. The low engine-out emissions can also make power-robbing exhaust aftertreatment devices unnecessary, thereby improving fuel efficiency. Unfortunately, PCCI combustion is difficult to control because the combustion depends strongly on the complex ignition kinetics of the fuel.
MEC is addressing this problem by using fast-response pressure sensors to provide real-time feedback on the combustion phasing. That real-time control signal is being applied in conjunction with a high-pressure electronic fuel injection system to stabilize PCCI combustion. MEC is designing the engine controller software, implementing the controller hardware, and performing engine dynamometer testing to demonstrate gains in engine performance and emissions.