Strange nonchaos in self-excited singing flames

TL;DR

This paper presents the first experimental evidence of strange nonchaotic attractors in an autonomous laboratory system, revealing a new dynamical transition route from order to chaos.

Contribution

It demonstrates the existence of SNA in a self-excited thermoacoustic system, expanding understanding of nonlinear dynamics in autonomous systems.

Findings

Evidence of SNA in a natural, autonomous system.

Transition from quasiperiodicity to chaos via SNA.

Confirmation through nonlinear characterization methods.

Abstract

We report the first experimental evidence of strange nonchaotic attractor (SNA) in the natural dynamics of a self-excited laboratory-scale system. In the previous experimental studies, the birth of SNA was observed in quasiperiodically forced systems; however, such an evidence of SNA in an autonomous laboratory system is yet to be reported. We discover the presence of SNA in between the attractors of quasiperiodicity and chaos through a fractalization route in a laboratory thermoacoustic system. The observed dynamical transitions from order to chaos via SNA is confirmed through various nonlinear characterization methods prescribed for the detection of SNA.