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Title: Quantifying liquid boundary and vapor distributions in a fuel spray by rainbow schlieren deflectometry

The rainbow schlieren deflectometry (RSD) technique is used to determine the liquid boundary and the fuel volume fraction distributions in the vapor region of a high-pressure fuel spray. Experiments were conducted in a constant pressure flow vessel, whereby a customized single-hole common-rail diesel injector is used to introduce n-heptane fuel into a coflow of low-speed ambient air at two different test conditions. Only the quasi-steady period of the fuel spray is considered, and multiple injections are performed to acquire statistically significant data at an image acquisition rate of 20 kHz. An algorithm to identify the liquid boundary using intensity recorded by the RSD images is presented. The results are compared against measurements obtained by the Mie scattering technique. Our results demonstrate that the RSD can be a powerful optical diagnostics technique to simultaneously quantify both the vapor and liquid regions in the high-pressure fuel sprays.
 [1] ;  [1] ;  [1]
  1. Univ. of Alabama, Tuscaloosa, AL (United States). Mechanical Engineering Dept.
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Applied Optics
Additional Journal Information:
Journal Volume: 56; Journal Issue: 30; Journal ID: ISSN 1559-128X
Optical Society of America
Research Org:
Univ. of Alabama, Tuscaloosa, AL (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE); United States Army Tank Automotive Research, Development and Engineering Center (TARDEC)
Country of Publication:
United States
42 ENGINEERING; 33 ADVANCED PROPULSION SYSTEMS; Lasers; Combustion diagnostics; Moiré techniques; fuel-air mixing; Diesel injection
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1399637