A Study on Laminar Lifted Jet Flames for Diluted Methane in Co-flow Air
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The laminar lifted jet flames for methane diluted with helium and nitrogen in co-flow air have been investi-gated experimentally. Such jet flames could be lifted in both buoyancy-dominated and jet momentum dominated regimes (even at nozzle exit velocities much higher than stoichiometric laminar flame speed) despite the Schmidt number less than unity. Chemiluminescence intensities of OH* radical (good indicators of heat release rate) and the radius of curvature for tri-brachial flame were measured using an intensified charge coupled device (ICCD) camera and digital video camera at various conditions. It was shown that, an increase in OH* concentration causes increase of edge flame speed via enhanced chemical reaction in buoyancy dominated regime. In jet momentum dominated regime, an increase in radius of curvature in addition to the increased OH* concentration stabilizes such lifted flames. Stabilization of such lifted flames is discussed based on the stabilization mechanism.
Abstract
The laminar lifted jet flames for methane diluted with helium and nitrogen in co-flow air have been investi-gated experimentally. Such jet flames could be lifted in both buoyancy-dominated and jet momentum dominated regimes (even at nozzle exit velocities much higher than stoichiometric laminar flame speed) despite the Schmidt number less than unity. Chemiluminescence intensities of OH* radical (good indicators of heat release rate) and the radius of curvature for tri-brachial flame were measured using an intensified charge coupled device (ICCD) camera and digital video camera at various conditions. It was shown that, an increase in OH* concentration causes increase of edge flame speed via enhanced chemical reaction in buoyancy dominated regime. In jet momentum dominated regime, an increase in radius of curvature in addition to the increased OH* concentration stabilizes such lifted flames. Stabilization of such lifted flames is discussed based on the stabilization mechanism.
참고문헌 (11)
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