This paper summarizes passive methods used to improve the stability of low-emission combustors in stationary power gas turbines. Common passive methods are reviewed, including discussion of control model concepts, application of simple time-lag models, and a review of acoustic dampers. Applications of time-lag modie cations are presented, and limitations of this approach are discussed. Nyquist analysis is used to show how changing the time lag can be confounded by the presence of multiple acoustic modes. Experimental results demonstrating the frequency shifts predicted by Nyquist analysis are also shown. Stabilizing effects of distributed time lags are discussed, along with some e eld applications. A review of acousticdampers showsthat these devices are not widely applied in stationary engines compared to rocket or afterburner combustors, but have shown good results where applied. Nomenclature ¤ AB;C; D, = combustor sections and the acoustic E; F; G transfer matrices that represent these sections; elements of these 2 £2 matrices are identie ed using subscripts Ai;j where i D0;1 and j D0;1 c
No takes yet. Share an insight, caveat, or question.
Richards et al. (2003) studied this question.