Emissions reduction using multiple stage diesel combustion

Emissions characteristics of a new low-NO, diesel combustion concept termed MULDIC (MULtiple stage DIesel Combustion), were examined under high load c onditions. In conventional diesel combustion, a near-stoichiometric mixture is formed during the ignition delay, which results in a large amount of NO x generated during the ensuing premixed combustion. Moreover, there is also a region of stoichiometric mixture formed when fuel mixes with air in diff usion combustion, where NOx is also produced. In MULDIC, premixed combustio n and diffusion combustion are separated in time, and optimized independent ly. As a result, NOx emissions from MULDIC were reduced to less than half t he values typical of conventional diesel combustion, at the same fuel consu mption.