Kasthuri Praveen, Unni Vishnu R, Sujith R I
Department of Aerospace Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
Department of Mechanical and Aerospace Engineering, University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093, USA.
Chaos. 2019 Apr;29(4):043117. doi: 10.1063/1.5095401.
We investigate the route to self-excited thermoacoustic instability in a laminar flow multiple flame matrix burner. With an increase in the equivalence ratio, the thermoacoustic system that is initially quiet (stable operation) transitions to limit cycle oscillations through two distinct dynamical states, namely, bursting oscillations and mixed mode oscillations. The acoustic pressure oscillations transition from quiescence to large amplitudes during bursting oscillations. Such high amplitude bursting oscillations that occur well ahead of the onset of limit cycle oscillations can potentially cause structural damage. The thermoacoustic system exhibits hysteresis. The transition to limit cycle oscillations is replicated in a phenomenological model containing slow-fast time scales.
我们研究了层流多火焰矩阵燃烧器中自激热声不稳定性的途径。随着当量比的增加，最初安静（稳定运行）的热声系统通过两种不同的动态状态转变为极限环振荡，即爆发振荡和混合模式振荡。在爆发振荡期间，声压振荡从静止转变为大幅度振荡。在极限环振荡开始之前就出现的这种高幅度爆发振荡可能会导致结构损坏。热声系统表现出滞后现象。在包含快慢时间尺度的唯象模型中再现了向极限环振荡的转变。
