Advanced combustion: Optical investigations in a single cylinder engine

Aim & Objectives:
Visualize fuel films on the piston surface and soot precursors within the combustion chamber to understand the cause and effect relationship between fuel films and particle formation.

Links to the results:
Deliverables:
D1.6 Report on optical diagnostics.
D1.10 Optical Diagnostics for Fuel-Films.

Presentation: Application of optical diagnostic techniques in a single cylinder engine by Jan Niklas Geiler – Bosch

LIF for fuel film quantification

Experimental setup and principle
Red shift in spectrum enables correction  of temperature dependency of the fluorescence signal

Tracer characterization
Enables quantitative fuel film measurements with different tracers.

Results

High-speed sequence showing spray, flame front, and soot luminosity

Soot precursor LIF and LII

Experimental setup and principle

Principle
Three laser wavelengths 266, 355, and 532 nm are used to visualize different size classes of soot precursors. 1064 nm is used to visualize soot.

Results

Single shots of PAH LIF images, from individual combustion events (upper row 1^st cycle, lower row 2^nd cycle).

Infrared-Absorption to visualize water

Aim & Objectives
Visualize and quantify water on the cylinder liner.

Principle
Measurements at two wavelengths to eliminate losses due to scattering. 

Experimental setup

Results

Endoscopic investigations in a thermodynamic engine

Aim & Objectives
Transfer of the measurement technique from the optical engine to a thermodynamic engine.

Experimental setup

Results

References and nomenclature

  • Geiler, J.N., Bildgebende Messung der Kraftstoffwandfilmdicke durch laserinduzierte Fluoreszenz: 978-3-8440-6721-7, 2019 ØGeiler, J.N., Grzeszik, R., Bossmeyer, T., Kaiser, S.A., Investigation of the fuel property influence on number of emitted particles and their size distribution in a gasoline engine with direct injection 20th ETH-Conference on Combustion Generated Nanoparticles, 2016 ØGeiler,
  • J.N., Grzeszik, R., Bossmeyer, T., Kaiser, S.A., Investigation of the fuel property influence on number of emitted particles and their size distribution in a gasoline engine with direct injection New and emerging technologies: Impact on air quality and climate, 2016
  • Geiler, J.N., Grzeszik, R., Bossmeyer, T., Kaiser, S.A., Weiterentwicklung der laser-induzierten Fluoreszenz (LIF) zur quantitativen innermotorischen Wandfilmmessung Motorische Verbrennung – Aktuelle Probleme und moderne Lösungansätze (XIII. Tagung), 2017
  • Geiler, J.N., Grzeszik, R., Quaing, S., Manz, A., Kaiser, S.A., Development of laser-induced fluorescence to quantify in-cylinder fuel wall-films International Journal of Engine Research, 2017
  • Geiler, J.N., Grzeszik, R., Manz, A., Mansbart, M.,  Further development of laser-induced fluorescence (LIF) to quantify in-cylinder fuel wall films Engine Combustion and Alternative Concepts – ENCOM 2019, 2019

LIF: Laser-induced fluorescence
LII: Laser-induced incandescence
PAH: Polycyclic aromatic hydrocarbons