Patent ID: 8275538
Filing Date: 2012-09-25
Classification: F02B,F02D,F02P,Y02T

Abstract:
1. A system, comprising: an engine having at least a first and second cylinder; each of the first and second cylinders having a liquid fuel injector and a gaseous fuel injector coupled thereto; a turbocharger coupled to the engine; and a control system coupled to the engine, the control system having a computer storage medium with instructions encoded thereon, the instructions comprising: instructions to, during a first combustion event from rest of engine starting, inject gaseous fuel to the first cylinder from the gaseous fuel injector at least during or before an intake stroke of an engine cycle of the first cylinder to form a well-mixed overall lean air-fuel mixture; instructions to initiate spark combustion spark combustion of at least the injected gaseous fuel in the first cylinder; and instructions to, during a second combustion event immediately following the first combustion event in a firing order of the engine, inject gaseous fuel to the second cylinder from the gaseous fuel injector at least during or before an intake stroke of an engine cycle of the second cylinder to form a well-mixed overall lean air-fuel mixture and to directly inject liquid fuel from the liquid fuel injector to the second cylinder at least during one of a compression and expansion stroke of the engine cycle of the second cylinder to at least form a rich air-fuel cloud near the spark plug; and instruction to initiate spark combustion of the injected fuels in the second cylinder.