Simultaneous high-speed formaldehyde PLIF and schlieren imaging of multiple injections from an ECN Spray D injector
Maes N, Sim HS, Weiß L, Pickett L (2021)
Publication Type: Conference contribution
Publication year: 2021
Publisher: American Society of Mechanical Engineers (ASME)
Conference Proceedings Title: ASME 2020 Internal Combustion Engine Division Fall Technical Conference, ICEF 2020
Event location: Virtual, Online
ISBN: 9780791884034
Abstract
The interaction of multiple injections in a diesel engine facilitates a complex interplay between freshly introduced fuel, previous combustion products, and overall combustion. To improve understanding of the relevant processes, high-speed Planar Laser-Induced Fluorescence (PLIF) with 355-nm excitation of formaldehyde and Polycyclic Aromatic Hydrocarbon (PAH) soot precursors is applied to multiple injections of n-dodecane from Engine Combustion Network Spray D, characterized by a converging 189-µm nozzle. High-speed schlieren imaging is applied simultaneously with 50-kHz PLIF excitation to visualize the spray structures, jet penetration, and ignition processes. For the first injection, formaldehyde (as an indicator of low-temperature chemistry) is first found in the jet periphery, after which it quickly propagates through the center of the jet, towards the jet head prior to high-temperature ignition. At second-stage ignition, downstream formaldehyde is consumed rapidly and upstream formaldehyde develops into a quasi-steady structure for as long as the momentum flux from the injector continues. Since the first injection in this work is relatively short, differences to a single long injection are readily observed, ultimately resulting in high-temperature combustion and PAH structures appearing farther upstream after the end of injection. For the second injection in this work, the first formaldehyde signal is significantly advanced because of the entrained high-temperature combustion products, and an obvious premixed burn event does not occur. The propensity for combustion recession after the end of the first injection changes significantly with ambient temperature, thereby affecting the level of interaction between the first- and second injection.
Authors with CRIS profile
Involved external institutions
United States (USA) (US)How to cite
APA:
Maes, N., Sim, H.S., Weiß, L., & Pickett, L. (2021). Simultaneous high-speed formaldehyde PLIF and schlieren imaging of multiple injections from an ECN Spray D injector. In ASME 2020 Internal Combustion Engine Division Fall Technical Conference, ICEF 2020. Virtual, Online: American Society of Mechanical Engineers (ASME).
MLA:
Maes, Noud, et al. "Simultaneous high-speed formaldehyde PLIF and schlieren imaging of multiple injections from an ECN Spray D injector." Proceedings of the ASME 2020 Internal Combustion Engine Division Fall Technical Conference, ICEF 2020, Virtual, Online American Society of Mechanical Engineers (ASME), 2021.
BibTeX: Download