Chemical and/or physical characteristics i.e. cetane number, determining method for diesel internal-combustion engine, involves carrying out injection of fuel, and determining measure for fuel characteristics from shifting combustion state

摘要

The method involves using a device of a diesel internal-combustion engine for determining a combustion state. A cylinder of the internal-combustion engine is operated temporally and limited in a test operation, in which pre-injection is suppressed during unchanged main injection. Injection of fuel i.e. diesel, is carried out in a normal operation in the form of pre-injection and main injection during compression and/or combustion strokes, where a measure for the chemical and/or physical characteristics of the fuel is determined from shifting the combustion state. Independent claims are also included for the following: (1) a method for compensation of dispersion of chemical and/or physical characteristics of a fuel for a diesel internal-combustion engine against a reference fuel (2) a computer program having instructions to perform a method for determining chemical and/or physical characteristics of fuel for a diesel internal-combustion engine.