Measurement of the equivalence ratio in the spark gap region of a gasoline direct injection engine with spark emission spectroscopy and tracer-LIF
In: SAE Technical Paper Series 2004-01-1916, Jg. SP-1891 (2004) ; Direct Fuel Injection, Engine Diagnostics, and New Developments in Powertrain Tribology, CVT, AFT & Fuel Economy, S. 9-17
Zeitschriftenaufsatz / Fach: Maschinenbau
The complexity of the mixt. formation in direct injection engines requires - according to a suitable mixt. transportation and vaporization of the fuel - detailed knowledge of the in-cylinder processes to reliably place an ignitable mixt. at ignition timing near the spark plug for any speed and load. Two different optical measurement techniques were adapted to a single cylinder engine and the spray propagation was obsd. from the start of injection until ignition. 3-Pentanone tracer-LIF signals (laser-induced fluorescence) and CN spark emission signals were detected simultaneously to get information about the local equivalence ratio at the spark plug and compare the two methods. While there is a good correlation for homogeneous operating conditions of the engine, the results diverge in the stratified mode.