title: Stochastic bifurcations in a prototypical thermoacoustic system.
abstract: We study the influence of noise in a prototypical thermoacoustic system, which represents a nonlinear self-excited bistable oscillator. We analyze the time series of unsteady pressure obtained from a horizontal Rijke tube and a mathematical model to identify the effect of noise. We report the occurrence of stochastic bifurcations in a thermoacoustic system by tracking the changes in the stationary amplitude distribution. We observe a complete suppression of a bistable zone in the presence of high intensity noise. We find that the complete suppression of the bistable zone corresponds to the nonexistence of phenomenological (P) bifurcations. This is a study in thermoacoustics to identify the parameter regimes pertinent to P bifurcation using the stationary amplitude distribution obtained by solving the Fokker-Planck equation.
authors.affiliation: Department of Aerospace Engineering, IIT Madras, Chennai, India.
authors.forename: E A
authors.initials: EA
authors.lastname: Gopalakrishnan
authors.affiliation: Department of Aerospace Engineering, IIT Madras, Chennai, India.
authors.forename: J
authors.initials: J
authors.lastname: Tony
authors.affiliation: Department of Aerospace Engineering, IIT Madras, Chennai, India.
authors.forename: E
authors.initials: E
authors.lastname: Sreelekha
authors.affiliation: Department of Aerospace Engineering, IIT Madras, Chennai, India.
authors.forename: R I
authors.initials: RI
authors.lastname: Sujith