Abstract
The established tracer laser-induced fluorescence (LIF) technique was newly adapted for the quantitative visualization of hydrogen inside an optically accessible hydrogen engine to investigate the processes of hydrogen-injection, mixture formation, ignition and combustion at motor-relevant operating points. Trimethylamine (TMA) has been seeded to the hydrogen and was thus used as a tracer for hydrogen when applying the LIF technique. End of injection (EOI) was varied at a constant speed of 2000 rpm and a load of 2 bar (IMEP) which represents typical part load condition. The results visualize the influence of EOI on the mixture formation, ignition and the beginning of combustion. The comparison of the visual results of four operating points shows how long it takes even in the case of hydrogen to get a homogeneous mixture at spark timing. Additionally, conventional engine data such as cylinder pressure, temperature, consumption, emissions etc. have been measured. Rough running engine due to uneven distribution in the region of the spark plug could be explained by single-shot images.
