TY - JOUR
T1 - Reconstruction of heat release response of partially premixed flames
AU - Kim, Kyu Tae
AU - Lee, Jong Guen
AU - Quay, Bryan D.
AU - Santavicca, Domenic A.
N1 - Funding Information:
Funding for this research was provided by the Department of Energy University Coal Research Program through Contract # DE-FG26-07NT43069 and the National Science Foundation through Award #0625970.
PY - 2011/2
Y1 - 2011/2
N2 - The forced response of a swirl-stabilized, partially premixed flame to inlet velocity and equivalence ratio oscillations was experimentally investigated in a model lean premixed gas turbine combustor. The responses of a premixed flame to three different forcing mechanisms were studied: velocity oscillations, equivalence ratio oscillations, and the combination of velocity and equivalence ratio oscillations. The overall heat release response of the flame was determined from measurements of the CH* chemiluminescence emission intensity from the entire flame, while the response of the spatially distributed heat release was determined from phase-synchronized chemiluminescence images. In addition, simultaneous measurements were made of the inlet velocity and equivalence ratio oscillations using the 2-microphone method and an IR absorption technique, respectively. The results show that in the linear regime, the response of a partially premixed flame to simultaneous velocity and equivalence ratio oscillations can be reconstructed from independent measurements of the flame's response to velocity oscillations and to equivalence ratio oscillations using a vector summation method. This is the first experimental demonstration of a 2-input 1-output model of a swirl-stabilized partially premixed flame. It suggests that the response of a partially premixed flame is governed by four physical parameters (i.e., the oscillation frequency, the amplitude of velocity oscillation, the amplitude of equivalence ratio oscillation, and the phase difference between the two oscillations). As a result, the heat release response of a partially premixed flame can be amplified or damped, depending on the phase difference between the velocity and equivalence ratio oscillations at the combustor inlet.
AB - The forced response of a swirl-stabilized, partially premixed flame to inlet velocity and equivalence ratio oscillations was experimentally investigated in a model lean premixed gas turbine combustor. The responses of a premixed flame to three different forcing mechanisms were studied: velocity oscillations, equivalence ratio oscillations, and the combination of velocity and equivalence ratio oscillations. The overall heat release response of the flame was determined from measurements of the CH* chemiluminescence emission intensity from the entire flame, while the response of the spatially distributed heat release was determined from phase-synchronized chemiluminescence images. In addition, simultaneous measurements were made of the inlet velocity and equivalence ratio oscillations using the 2-microphone method and an IR absorption technique, respectively. The results show that in the linear regime, the response of a partially premixed flame to simultaneous velocity and equivalence ratio oscillations can be reconstructed from independent measurements of the flame's response to velocity oscillations and to equivalence ratio oscillations using a vector summation method. This is the first experimental demonstration of a 2-input 1-output model of a swirl-stabilized partially premixed flame. It suggests that the response of a partially premixed flame is governed by four physical parameters (i.e., the oscillation frequency, the amplitude of velocity oscillation, the amplitude of equivalence ratio oscillation, and the phase difference between the two oscillations). As a result, the heat release response of a partially premixed flame can be amplified or damped, depending on the phase difference between the velocity and equivalence ratio oscillations at the combustor inlet.
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U2 - 10.1080/00102202.2010.503205
DO - 10.1080/00102202.2010.503205
M3 - Article
AN - SCOPUS:78650184738
SN - 0010-2202
VL - 183
SP - 122
EP - 137
JO - Combustion science and technology
JF - Combustion science and technology
IS - 2
ER -