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Title: Swirl number effects on the blowoff limits of swirl-stabilized flames
This work focused on understanding how swirl influences the blowoff limit and process in lean-premixed, swirl-stabilized flames. Two initial equivalence ratios (Ф0 = 0.8 and 1.0) were used to study the effect of swirl number (S = 0.80, 0.95, 1.15, and 1.43) on the lean blowoff limits. It was seen that at higher Ф0, the blowoff equivalence ratio of flames with lower swirl levels was typically more sensitive to bulk flow velocities than flames stabilized at lower Ф0. The blowoff Ф of flames stabilized at higher swirl levels did not vary much with an increase in bulk flow velocity. Global CH* chemiluminescence was done to study the lean blowoff process further. At lower Ф0 and swirl levels, the occurrence of the extinction/reignition events in the shear layers seemed more prominent.  more » « less
Award ID(s):
1749679
PAR ID:
10536030
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Combustion Institute
Date Published:
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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