Patent ID: 8532911
Filing Date: 2013-09-10
Classification: F02D,Y02T

Abstract:
1. A method for controlling combustion in a diesel engine, said method comprising: running the engine with a fuel of an unknown cetane number; estimating the cetane number of the fuel based on engine performance data and ignition delay, including estimating the cetane number during engine deceleration conditions by skipping fuel injection on some cycles in some cylinders, computing pressure ratios for cycles with fuel injection and cycles without fuel injection, and comparing the pressure ratios; using the estimated cetane number in a controller to make adjustments to engine inputs to improve combustion in the engine; and computing a combustion phasing value for each cylinder using cylinder pressure data during engine operation and using the combustion phasing value to adjust start of injection timing, where the combustion phasing value is defined as the crank angle position at which a certain percentage of the fuel in a particular cylinder has been burned.