The Nonlinearity during Start-Oscillation of Thermo-Acoustic Instability in Rijke-Type Combustor
In order to study the nonlinearity during the start-oscillation of thermo-acoustic instability, an experimental setup was built. The growing process of nonlinearity during the start-oscillation of thermo-acoustic instability was captured and analyzed. Experimental results revealed that after a suitable resonance mode corresponding to the structural of the combustor was selected, the pressure perturbations inside the combustor grow in amplitude into a very large amplitude and self-excited oscillation in a very short period of time. Then, slowly, the nonlinear effects adjust the shapes of pressure waveforms and amplify the oscillations. Ultimately, a limit-cycle oscillation with smooth and uniform pressure waveforms was obtained, and the acoustic waves exhibit only the main resonance mode, damping other modes of instability.
Helen Zhang, Gang Shen and David Jin
G. N. Li et al., "The Nonlinearity during Start-Oscillation of Thermo-Acoustic Instability in Rijke-Type Combustor", Advanced Materials Research, Vols. 204-210, pp. 1158-1161, 2011