Mode-Locked Rotating Detonation Waves: Experiments and a Model Equation

TL;DR

This paper presents experimental observations and a new model for rotating detonation waves in engines, revealing complex dynamics and bifurcations similar to those in driven-dissipative systems.

Contribution

It introduces a novel model recasting the Majda detonation analog as an autowave to explain observed detonation wave dynamics.

Findings

Observation of rich instabilities and bifurcations in detonation waves

Development of a model capturing mode-locking and bifurcation behavior

Identification of competition between energy release, dissipation, and gain recovery

Abstract

Direct observation of a Rotating Detonation Engine combustion chamber has enabled the extraction of the kinematics of its detonation waves. These records exhibit a rich set of instabilities and bifurcations arising from the interaction of coherent wave fronts and global gain dynamics. We develop a model of the observed dynamics by recasting the Majda detonation analog as an autowave. The solution fronts become attractors of the engine; i.e., mode-locked rotating detonation waves. We find that detonative energy release competes with dissipation and gain recovery to produce the observed dynamics and a bifurcation structure common to driven-dissipative systems, such as mode-locked lasers.