Numerical simulation of finite disturbances interacting with laminar premixed flames

Abstract

Compression waves can be generated during combustion processes and subsequently interact with flames to augment their behaviour. The study of these interactions thus far has been limited to shock and expansion waves only. In this study, the interaction of finite compression waves with a perturbed laminar flame is investigated using numerical simulations of the compressible Navier–Stokes equations with single-step chemical kinetics. The interaction is characterised using three independent parameters: the compression wavelength, the pressure ratio of the disturbance, and the perturbation amplitude of the flame interface. The results reveal a wide range of behaviours in terms of flame length and heat release rate that could occur during such an interaction. The results are compared to the classical reactive Richtmyer–Meshkov instability and the role of baroclinic torque and vorticity generation are shown to be primary drivers of the flow instability.

KEYWORDS:

• finite disturbances
• laminar premixed combustion
• perturbed flame
• Richtmyer–Meshkov
• wavelet collocation method

Acknowledgements

This work has been approved for unlimited release: LA-UR-17-27654.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The computational resources in this paper are partially supported by the HPC@ISU equipment at Iowa State University, some of which has been purchased through funding provided by the National Science Foundation under Major Research Instrumentation [grant number CNS 1229081]; and the Cancer Research Institute [grant number 1205413].