1. 제 목 : A Study of the Role of Equivalence Ratio Fluctuations During Unstable


Combustion in a Lean Premixed Combustor





2. 연 사 : Dr. Jong Guen Lee


Department of Mechanical and Nuclear Engineering


Penn State University





3. 일 시 : 9월 20일 (수) 오후 4시-5시





4. 장 소 : 301동 1512호





5. 내 용




















5.The mechanism of unstable combustion was studied in a Solar Turbines Centaur 50 injector. This injector previously exhibited unstable combustion over a limited range of operating conditions in full-engine tests which were successfully eliminated by redesigning the injector based on a fuel time lag analysis. The objectives of the work reported in this paper were to assess the role of equivalence ratio fluctuations in the original instabilities and to determine the actual effect of the redesigned injector on the instability mechanism.


To address these issues, tests were conducted on a full-scale Centaur 50 injector in an optically accessible single injector test facility designed to replicate the ~460 Hz instability observed in the full-engine tests. The instability characteristics were determined from high frequency response pressure transducer measurements, phase synchronized chemiluminescence imaging and high frequency response infrared absorption equivalence ratio measurements. These measurements were also used to identify the mechanisms which play a role in the unstable combustion process. The effect of the injector geometry change was determined from chemiluminescence-based flame response measurements and laser induced fluorescence measurements of the fuel distribution at the combustor inlet.


The results of these measurements are used to clarify the effect of the design change on the stability characteristics of the Centaur 50 injector and to suggest strategies for suppressing instabilities in other injector configurations.





5. 문 의 : 기계항공공학부 정석호 교수 (☏ : 880-7114)