caa a22 4500 606196986 CHVBK 20210128100927.0 cr unu---uuuuu 210128e20150101xx s 000 0 eng 10.1007/s00348-014-1865-7 doi (NATIONALLICENCE)springer-10.1007/s00348-014-1865-7 Laser-induced incandescence measurements in a fired diesel engine at 3kHz [Elektronische Daten] [I. Boxx, O. Heinold, K. Geigle] Laser-induced incandescence (LII) was performed at 3kHz in an optically accessible cylinder of a fired diesel engine using a commercially available diode-pumped solid-state laser and an intensified CMOS camera. The resulting images, acquired every 3° of crank angle, enabled the spatiotemporal tracking of soot structures during the expansion/exhaust stroke of the engine cycle. The image sequences demonstrate that soot tends to form in thin sheets that propagate and interact with the in-cylinder flow. These sheets tend to align parallel to the central axis of the cylinder and are frequently wrapped into conical spirals by aerodynamic swirl. Most of the soot is observed well away from the cylinder walls. Quantitative soot measurements were beyond the scope of this study but the results demonstrate the practical utility of using kHz-rate LII to acquire ensemble-averaged statistical data with high crank angle resolution over a complete engine cycle. Based on semi-quantitative measures of soot distribution, it was possible to identify soot dynamics related to incomplete charge exchange. This study shows that long-duration, multi-kHz acquisition rate LII measurements are viable in a fired diesel engine with currently available laser and camera technology, albeit only in the expansion and exhaust phase of the cycle at present. Furthermore, such measurements yield useful insight into soot dynamics and therefore constitute an important new tool for the development and optimization of diesel engine technology. Springer-Verlag Berlin Heidelberg, 2014 Boxx I. Deutsches Zentrum für Luft- und Raumfahrt e.V., Pfaffenwaldring 38-40, 70569, Stuttgart, Germany aut Heinold O. Robert Bosch GmbH, Robert-Bosch-Platz 1, 70839, Gerlingen, Germany aut Geigle K. Deutsches Zentrum für Luft- und Raumfahrt e.V., Pfaffenwaldring 38-40, 70569, Stuttgart, Germany aut Experiments in Fluids Springer Berlin Heidelberg 56/1(2015-01-01), 1-10 0723-4864 56:1<1 2015 56 348 https://doi.org/10.1007/s00348-014-1865-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00348-014-1865-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Boxx I. Deutsches Zentrum für Luft- und Raumfahrt e.V., Pfaffenwaldring 38-40, 70569, Stuttgart, Germany aut NATIONALLICENCE 700 1- Heinold O. Robert Bosch GmbH, Robert-Bosch-Platz 1, 70839, Gerlingen, Germany aut NATIONALLICENCE 700 1- Geigle K. Deutsches Zentrum für Luft- und Raumfahrt e.V., Pfaffenwaldring 38-40, 70569, Stuttgart, Germany aut NATIONALLICENCE 773 0- Experiments in Fluids Springer Berlin Heidelberg 56/1(2015-01-01), 1-10 0723-4864 56:1<1 2015 56 348