By means of planar laser-induced fluorescence (PLIF) it is possible to perform measurements inside the combustion chamber of an optically accessible engine. Thus it is possible to investigate the mixture formation process of hydrogen engines qualitatively in two dimensions. Also quantitative measurements are possible, i.e. statements about the fuel/air-ratio distribution in the combustion chamber. To obtain these results not only PLIF measurements for normal engine operation with the built-in injection valve are necessary but also PLIF measurements with a premixed homogeneous tracer/fuel gas/air-mixture with a defined fuel/air-ratio. For most measurements a mixture of He and the selected tracer substance TEA was used. Part-load measurements can also be Made with a H2/TEA-mixture. Measurements at a high-pressure high-temperature cell have shown the dependencies of the used mixture concerning pressure, temperature and fuel/air-ratio (results not published up to now). The results of this PLIF measurement technique have been verified by directly measuring the fuel/air-ratio and the hydrogen concentration in the fired engine with Raman scattering. lt is possible to investigate the gas flow into the cylinder qualitatively and also to get correct values for the fuel/air-ratio distribution inside the combustion chamber if some boundary conditions are met during the measurements. Qualitative and quantitative PLIF measurements are therefore not only possible for hydrogen as a fuel gas but also for other fuel gases like natural gas. For other fuel gases it is necessary to determine the spectroscopic properties of these gases and the mixture of gas and tracer as it is done for hydrogen or helium and the tracer triethylamine. There are some items for further development of this measurement technique. First the mixing device for the generation of the gas/tracer-mixture has to be adapted to every measurement task, i.e. every engine which should be investigated, concerning gas and fluid flows to get only small measurement deviations and a small relative error of the predetermined fuel/air-ratio for the measurements with homogeneous air/gas-mixture. As stated above the residual gas fluorescence has to be investigated further.
Developing planar laser-induced fluorescence for the investigation of the mixture formation process in hydrogen engines
Entwicklung einer planaren laserinduzierten Floureszenzmessmethode für die Untersuchung des Mischungsbildungsprozesses in einem Wasserstoffmotor
2004
14 Seiten, 11 Bilder, 1 Tabelle, 12 Quellen
Aufsatz (Konferenz)
Englisch
Raman-Effekt , Verbrennungsraum , Kraftstoff-Luft-Gemisch , Einspritzvorrichtung , Tracer , Hochdruck (Mechanik) , Hochtemperatur , Teillast , Gasströmung , Randbedingung , Brenngas , Erdgas , spektroskopische Untersuchung , relativer Fehler , fluide Strömung , Mischvorrichtung , LIF (laserinduzierte Fluoreszenz) , Wasserstoffmotor
British Library Conference Proceedings | 2004
|SAE Technical Papers | 2004
|British Library Online Contents | 1996
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