| 摘要 |
[Problem] To reduce the number of steps needed to produce a waveform of the heat generation rate of an internal combustion engine, and to make it easier than conventionally possible to estimate and evaluate the ignition delay period while maintaining the required accuracy. [Solution] The period from the spark plug-piloted ignition to the air-fuel mixture self-ignition is defined as the ignition delay period τ, which is one of the characteristic values of a heat generation rate waveform. If the self-ignition timing (FA) of the air-fuel mixture is advanced of top-dead center of the piston (BTDC), the ignition delay period τ is estimated on the basis of the in-cylinder fuel density (ρfuel@SA) at the piloted ignition timing (FA), and if the air-fuel mixture self-ignition timing (FA) is retarded from top dead center of the piston (ATDC), then the aforementioned ignition delay period τ is estimated on the basis of the in-cylinder fuel density (ρfuel@FA) at the self-ignition timing (FA). A heat generation rate waveform is produced using the estimated ignition delay time τ. |
