Investigation of in-cylinder soot formation in a DISI engine during transient operation by simultaneous endoscopic PIV and flame imaging. (March 2023)

• Record Type: Journal Article
• Authors: Fach, Christian; Rödel, Nico; Schorr, Jürgen; Krüger, Christian; Dreizler, Andreas; Böhm, Benjamin
• Is Part Of: International journal of engine research. Volume 24:Number 3(2023)
• Page Start: 1175
• Page End: 1189
• Publication Date: 2023-03
• Subjects: High-speed particle image velocimetry -- spray visualization -- flame propagation -- soot formation -- endoscopic -- internal combustion engine -- transient engine operation; Engines -- Periodicals; 629.25
• DOI: 10.1177/14680874221079764
• Languages: English
• ISSNs: 1468-0874

Abstract

A single-cylinder full-metal engine with a real combustion chamber geometry was used to investigate particulate number emissions resulting from transient engine operation. The formation of particulate number emissions depends on mixture formation influenced by the in-cylinder flow and injection, and the formation of fuel films on the in-cylinder walls. For the investigation of this multi-parameter process, simultaneous endoscopic PIV and combustion visualization were applied. Hence, the measurement techniques allowed the investigation of in-cylinder flow, flame propagation, and soot formation. The test rig was modified to apply a generic load step and a realistic tip-in with Miller cycle. The reproducibility of the engine parameters during the transient allowed statistical analysis and the comparison between steady-state operating points. Cause-and-effect chains concerning the formation of soot are concluded by correlation analysis of parameters extracted from the flow field, the flame propagation and the soot luminosity.