METHOD AND APPARATUS FOR MEASURING CONCENTRATION OF FUEL IN INTERNAL ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a method for measuring the concentration of fuel in an internal engine that can accurately measure the concentration of fuel in a combustion chamber without being affected by the evaporation characteristics of the fuel when a multiconstituent fuel is used as a target. SOLUTION: The apparatus for measuring the concentration of fuel in an internal engine comprises a pair of optical elements (3a, 3b) that is arranged with a specific interval at the combustion chamber of the internal engine that is operated by the multiconstituent fuel, a light intensity detection means (30) for detecting the intensity of light that is transmitted through the inside of the combustion chamber via the optical elements, and a fuel concentration-calculating means (40) for calculating the concentration of fuel in the space between the optical elements based on the intensity of transmission light that is detected by the light intensity detection means. The apparatus has a light source (1) for emitting light having a plurality of different wavelengths being absorbed by the fuel to the optical elements. The fuel concentration-calculating means simultaneously measures the intensity of the transmission light of at least two specific light in light having a plurality of wavelengths, and at the same time calculates fuel concentration in the space between the optical elements based on the transmission light intensity of the specific light.