Open AccessSingle-sensor filter-intensified fiber optic 4D tomographic CH* chemiluminesence flame measurements
Author(s) -
Cal Rising,
Jonathan Reyes,
Darin A. Knaus,
Danny Micka,
Brynmor J. Davis,
Vincent Belovich,
Kareem A. Ahmed
Publication year - 2021
Publication title -
applied optics
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 0.668
H-Index - 197
eISSN - 2155-3165
pISSN - 1559-128X
DOI - 10.1364/ao.425887
Subject(s) - combustion , optical fiber , optics , materials science , filter (signal processing) , fiber optic sensor , signal (programming language) , computer science , physics , chemistry , computer vision , organic chemistry , programming language
Chemiluminesence is one of the most common reacting flow visualization techniques, in which a narrowband wavelength associated with species radicals is captured on an image sensor. This technique can provide key insights into flame physics, particularly when a full 3D field can be extracted. Tomographic imaging can capture 3D instantaneous information, but becomes impractical to use when the technique is extended to larger, heavier high-speed imaging equipment. This has resulted in many researchers using fiber-based endoscopes (FBE) to capture multiple views on a single image sensor. However, the introduction of the fiber bundle and corresponding equipment to image specific combustion radicals results in a low SNR imaging environment when captured at high repetition rates. Additionally, when varying equivalence ratios, the signal can become further diminished because the combustion radicals signal weakens at fuel rich and fuel lean conditions. Therefore, this work determines the efficacy of using a filter-intensified FBE approach to capture the CH* radical of a hydrocarbon flame under varying equivalence ratio conditions by comparing the resulting reconstructions to previous quantitative flame measurements.