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Title: Peering through the flames: imaging techniques for reacting aluminum powders

Abstract

Combusting metals burn at high temperatures and emit high-intensity radiation in the visible spectrum which can over-saturate regular imaging sensors and obscure the field of view. Filtering the luminescence can result in limited information and hinder thorough combustion characterization. A method for “seeing through the flames” of a highly luminescent aluminum powder reaction is presented using copper vapor laser (CVL) illumination synchronized with a high-speed camera. A statistical comparison of combusting aluminum particle agglomerate between filtered halogen and CVL illumination shows the effectiveness of this diagnostic approach. When ignited by an electrically induced plasma, aluminum particles are entrained as solid agglomerates that rotate about their centers of mass and are surrounded by emitted, burning gases. Furthermore, the average agglomerate diameter appears to be 160 micrometers when viewed with standard illumination and a high-speed camera. But, a significantly lower diameter of 50 micrometers is recorded when imaged with CVL illumination. Our results advocate that alternative imaging techniques are required to resolve the complexities of metal particle combustion.

Authors:
 [1];  [1];  [1];  [2];  [3];  [4]
  1. Texas Tech Univ., Lubbock, TX (United States). Mechanical Engineering Dept.
  2. Texas Tech Univ., Lubbock, TX (United States). Chemical Engineering Dept.
  3. Texas A & M Univ., College Station, TX (United States). Electrical Engineering Dept.
  4. Idaho National Lab. (INL), Idaho Falls, ID (United States)
Publication Date:
Research Org.:
Idaho National Lab. (INL), Idaho Falls, ID (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1367530
Report Number(s):
INL/JOU-16-40543
Journal ID: ISSN 0003-6935; APOPAI
Grant/Contract Number:
AC07-05ID14517; W911NF-14-1-0250; 16-081
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Optics
Additional Journal Information:
Journal Volume: 56; Journal Issue: 9; Journal ID: ISSN 0003-6935
Publisher:
Optical Society of America (OSA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 47 OTHER INSTRUMENTATION; Thermites; visualization; high-speed imaging; alum

Citation Formats

Zepper, Ethan T., Pantoya, Michelle L., Bhattacharya, Sukalyan, Marston, Jeremy O., Neuber, Andreas A., and Heaps, Ronald J. Peering through the flames: imaging techniques for reacting aluminum powders. United States: N. p., 2017. Web. doi:10.1364/AO.56.002535.
Zepper, Ethan T., Pantoya, Michelle L., Bhattacharya, Sukalyan, Marston, Jeremy O., Neuber, Andreas A., & Heaps, Ronald J. Peering through the flames: imaging techniques for reacting aluminum powders. United States. doi:10.1364/AO.56.002535.
Zepper, Ethan T., Pantoya, Michelle L., Bhattacharya, Sukalyan, Marston, Jeremy O., Neuber, Andreas A., and Heaps, Ronald J. Fri . "Peering through the flames: imaging techniques for reacting aluminum powders". United States. doi:10.1364/AO.56.002535. https://www.osti.gov/servlets/purl/1367530.
@article{osti_1367530,
title = {Peering through the flames: imaging techniques for reacting aluminum powders},
author = {Zepper, Ethan T. and Pantoya, Michelle L. and Bhattacharya, Sukalyan and Marston, Jeremy O. and Neuber, Andreas A. and Heaps, Ronald J.},
abstractNote = {Combusting metals burn at high temperatures and emit high-intensity radiation in the visible spectrum which can over-saturate regular imaging sensors and obscure the field of view. Filtering the luminescence can result in limited information and hinder thorough combustion characterization. A method for “seeing through the flames” of a highly luminescent aluminum powder reaction is presented using copper vapor laser (CVL) illumination synchronized with a high-speed camera. A statistical comparison of combusting aluminum particle agglomerate between filtered halogen and CVL illumination shows the effectiveness of this diagnostic approach. When ignited by an electrically induced plasma, aluminum particles are entrained as solid agglomerates that rotate about their centers of mass and are surrounded by emitted, burning gases. Furthermore, the average agglomerate diameter appears to be 160 micrometers when viewed with standard illumination and a high-speed camera. But, a significantly lower diameter of 50 micrometers is recorded when imaged with CVL illumination. Our results advocate that alternative imaging techniques are required to resolve the complexities of metal particle combustion.},
doi = {10.1364/AO.56.002535},
journal = {Applied Optics},
number = 9,
volume = 56,
place = {United States},
year = {Fri Mar 17 00:00:00 EDT 2017},
month = {Fri Mar 17 00:00:00 EDT 2017}
}

Journal Article:
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