TY - JOUR
T1 - Acoustic characterization of an ethylene-fueled scramjet combustor with a cavity flameholder
AU - Lin, Kuo Cheng
AU - Jackson, Kevin
AU - Behdadnia, Robert
AU - Jackson, Thomas A.
AU - Ma, Fuhua
AU - Yang, Vigor
N1 - Funding Information:
This work was sponsored by the U.S. Air Force Research Laboratory (AFRL), Propulsion Directorate, under contract number F33615-03-D-2326 (Contract Monitor: Robert Behdadnia). Assistance from the air facility group of the AFRL is acknowledged. The authors would also like to thank Paul Kennedy (AFRL, Propulsion Directorate, Aerospace Propulsion Division), Matthew Streby and Steven Enneking (Taitech, Inc.) for their great assistance in rig operation, data acquisition, and hardware design and setup.
PY - 2010
Y1 - 2010
N2 - Past experience with ramjet engines suggests that combustion instabilities and associated flow oscillations may also occur in scramjet engines, although the problem has not been recognized and explored yet. The present work investigated thermoacoustic instabilities inside an ethylene-fueled scramjet combustor with a recessed-cavity flameholder. Detailed characterization was made of flame oscillation and acoustic motion using high-speed photography and pressure measurements. The effects of fuel/air equivalence ratio, fueling scheme, and simulated flight conditions on the stability characteristics in the engine flowpath were examined systematically. In addition, an analytical analysis based on the acoustic and convective feedback loops among the precombustion shock, fuel injection, and distributed flame was established to help understand and correlate the observed oscillation phenomena. The oscillation frequencies fall in a range of 100-400 Hz, with the upper bound dictated by the shock- flame coupling mechanism and the lower bound by the injector-flame interaction.
AB - Past experience with ramjet engines suggests that combustion instabilities and associated flow oscillations may also occur in scramjet engines, although the problem has not been recognized and explored yet. The present work investigated thermoacoustic instabilities inside an ethylene-fueled scramjet combustor with a recessed-cavity flameholder. Detailed characterization was made of flame oscillation and acoustic motion using high-speed photography and pressure measurements. The effects of fuel/air equivalence ratio, fueling scheme, and simulated flight conditions on the stability characteristics in the engine flowpath were examined systematically. In addition, an analytical analysis based on the acoustic and convective feedback loops among the precombustion shock, fuel injection, and distributed flame was established to help understand and correlate the observed oscillation phenomena. The oscillation frequencies fall in a range of 100-400 Hz, with the upper bound dictated by the shock- flame coupling mechanism and the lower bound by the injector-flame interaction.
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U2 - 10.2514/1.43338
DO - 10.2514/1.43338
M3 - Article
AN - SCOPUS:78649500683
VL - 26
SP - 1161
EP - 1169
JO - Journal of Propulsion and Power
JF - Journal of Propulsion and Power
SN - 0748-4658
IS - 6
ER -