METHOD FOR DETECTING THE ANTI-KNOCKING CAPACITY OF A FUEL IN AN INTERNAL COMBUSTION ENGINE

摘要

A method for detecting the anti-knocking capacity of a fuel in an internal combustion engine, which comprises the step of analyzing the single combustion cycles of the cylinders to be repeated until a counter reaches a respective threshold value; the step of calculating the mean spark advance operated by the internal combustion engine in the single combustion cycles of the cylinders that have allowed said counter to reach the respective threshold value; and the step of determining the anti-knocking capacity of the fuel as a function of the first counter that has reached the respective threshold value and as a function of the mean spark advance operated by the internal combustion engine in the single combustion cycles of the cylinders that have allowed said counter to reach the respective threshold value.

主权项

1. A method for detecting the anti-knocking capacity of a fuel in an internal combustion engine provided with a number of cylinders, the method comprising:
identifying a plurality of fuels as a function of their anti-knocking capacity; identifying a reference fuel among the plurality of fuels; an analysis step to analyze the single combustion cycles of the cylinders comprising the following sub-steps: determining a detonation index for each combustion; wherein the detonation index is calculated through the difference between a raw detonation index, which is correlated with the maximum amplitude of the intensity of the pressure waves generated in a cylinder during the combustion, and a reference value, which represents the maximum amplitude of the intensity of the pressure waves generated in the cylinder for each combustion cycle in the absence of detonating events; comparing the detonation index with a number of threshold values, which define a number of detonation intervals; each one of said detonation intervals defines detonating events, which substantially have the same intensity; and increasing a first counter associated with the detonation interval in which the detonation index is included; repeating the analysis step to analyze the single combustion cycles of the cylinders until the moment in which any one of the first counters reaches a respective limit value; calculating the mean spark advance operated by the internal combustion engine in the single combustion cycles of the cylinders that have allowed said first counter to reach the respective limit value; and determining the variation to be applied to the anti-knocking capacity of the reference fuel as a function both of the first counter that has reached the respective limit value and of the mean spark advance operated by the internal combustion engine in the single combustion cycles of the cylinders that have allowed said first counter to reach the respective limit value.