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Title: Effect of centerbody temperature on blowoff limits of a swirl-stabilized flame.
Swirl-stabilized flames are used in many gas turbine combustor configurations due to their enhanced static stability. The effects of combustor geometry, fuel composition, and bulk velocity on flame stability in swirling flows are well studied, but the effects of centerbody temperature have not been rigorously considered. The purpose of this study is to understand the impact of centerbody temperature on flame shape and dynamics. A newly instrumented variable-angle swirl-stabilized combustor was used to perform a repeatability study, and blowoff equivalence ratio was measured at centerbody temperatures ranging from 150 to 350°C and bulk velocities ranging from 16 to 55 m/s. Blowoff equivalence ratio generally decreases with centerbody temperature. Two structures were observed during blowoff: a cone shape and flame chugging. Blowoff equivalence ratio was consistently lower when the cone structure occurred, though the mechanism that excites these behaviors is still under investigation.  more » « less
Award ID(s):
1749679 2149667
PAR ID:
10536023
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Combustion Institute
Date Published:
Format(s):
Medium: X
Location:
Athens, GA
Sponsoring Org:
National Science Foundation
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