Diffusive–thermal oscillations of rich premixed hydrogen–air flames in a microflow reactor

Abstract

In this paper the dynamics of rich hydrogen–air flames in a microflow reactor with controlled temperature of the walls is investigated numerically using the thermal-diffusion model with two-step kinetics in one spatial dimension. It is found that as the parameters of the system are varied the sequence of bifurcation occurs leading to the formation of complex spatio-temporal patterns. These include pulsating, chaotic, mixed-mode and FREI (Flames with Repetitive Extinction and Ignition) oscillations. The critical parameter values for the existence of different dynamical regimes are found in terms of equivalence ratio and flow velocity.

Keywords:

• premixed flames
• stability
• microcombustion
• hydrogen–air flames
• flame dynamics

Acknowledgements

We are grateful to A.V. Kolobov, A.A. Polezhaev, and E.I. Volkov for fruitful discussion and valuable comments.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Ministry of Education and Science of the Russian Federation [Grant 14.Y26.31.0003]; the Far Eastern Federal University; the Russian Foundation for Basic Research [Grant 13-03-00282].