title: In-cylinder temperature measurements via time-correlated single-photon counting of toluene laser-induced fluorescence through a fiber-based sensor.
abstract: In a near-production internal combustion engine, the effective fluorescence lifetime of toluene was determined by time-correlated single-photon counting with a minimally invasive fiber-optic spark-plug sensor. The lifetime measurement provided continuous crank-angle-resolved measurements of gas temperature. Proof-of-concept experiments in a motored four-cylinder spark-ignition engine were evaluated with a time resolution of 500 μs, yielding temperature precision of 25 K (standard deviation) at top-dead center. In these experiments, 10% toluene was added to the nonfluorescent base fuel iso-octane. Fluorescence lifetimes were related to temperature via calibration measurements in a high temperature pressure vessel, with the data fitted to a functional dependence derived from a previously published phenomenological model.
authors.affiliation: IVG, Institute for Combustion and Gasdynamics, University of Duisburg-Essen, Duisburg 47057, Germany. eugen.friesen@uni-ue.de
authors.forename: Eugen
authors.initials: E
authors.lastname: Friesen
authors.forename: Christopher
authors.initials: C
authors.lastname: Gessenhardt
authors.forename: Sebastian A
authors.initials: SA
authors.lastname: Kaiser
authors.forename: Thomas
authors.initials: T
authors.lastname: Dreier
authors.forename: Christof
authors.initials: C
authors.lastname: Schulz