High-repetition-rate laser-induced fluorescence measurements of fuel and OH concentrations in internal combustion engines are demonstrated. Series of as many as eight fluorescence images, with a temporal resolution ranging from 10 μs to 1 ms, are acquired within one engine cycle. A multiple-laser system in combination with a multiple-CCD camera is used for cycle-resolved imaging in spark-ignition, direct-injection stratified-charge, and homogeneous-charge compression-ignition engines. The recorded data reveal unique information on cycle-to-cycle variations in fuel transport and combustion. Moreover, the imaging system in combination with a scanning mirror is used to perform instantaneous three-dimensional fuel-concentration measurements.
© 2002 Optical Society of America
Johan Hult, Mattias Richter, Jenny Nygren, Marcus Aldén, Anders Hultqvist, Magnus Christensen, and Bengt Johansson, "Application of a High-Repetition-Rate Laser Diagnostic System for Single-Cycle-Resolved Imaging in Internal Combustion Engines," Appl. Opt. 41, 5002-5014 (2002)