摘要:
A diesel engine (E) has a combustion chamber (C), a piston (T) movable in the chamber, air intake and exhaust valves (IV, EV), and a nozzle (N) injecting fuel into the combustion chamber. By controlling characteristics of an air-fuel mixture, emissions produced by combustion of the air-fuel mixture in the chamber are reduced to levels which satisfy the Tier 2 requirements established by the Environmental Protection Agency (EPA) for the engine. This may include controlling hydraulic flow characteristics through the nozzle, increasing the compression ratio within the combustion chamber, lowering the manifold air temperature (MAT), and retarding the start of fuel injection (SOI) within the chamber.