Repository logo
 

Multiscale analysis of head-on quenching premixed turbulent flames

Accepted version
Peer-reviewed

Type

Article

Change log

Authors

Ahmed, U 
Klein, M 
Chakraborty, N 

Abstract

jats:pMultiscale analysis of wall-bounded turbulent premixed flames is performed using three-dimensional direct numerical simulation data of flame-wall interaction (FWI). The chosen configuration represents head-on quenching of a turbulent statistically planar stoichiometric methane-air flame by an isothermal inert wall. Different turbulence intensities and chemical mechanisms have been analyzed. A bandpass filtering technique is utilised to analyze the influence of turbulent eddies of varying size and the statistics of vorticity and strain rate fields associated with them. It is found that the presence of the flame does not alter the mechanism of vortex stretching in turbulent flows when the flame is away from the wall, but in the case of FWI, the mechanism of vortex stretching is altered due to a reduction in the contribution from non-local strain, and the small scales of turbulence start to contribute to the flame straining process. The results indicate that small scale eddies do not contribute to the tangential strain rate when the flames are away from the walls, whereas the contribution from the small scales to the tangential strain rate increases when the flame is in the vicinity of the wall. It is also found that the choice of chemical mechanism does not influence the underlying fluid mechanical processes involved in FWI.</jats:p>

Description

Keywords

4012 Fluid Mechanics and Thermal Engineering, 40 Engineering, 4017 Mechanical Engineering, 4002 Automotive Engineering

Journal Title

Physics of Fluids

Conference Name

Journal ISSN

1070-6631
1089-7666

Volume Title

30

Publisher

AIP Publishing
Sponsorship
Engineering and Physical Sciences Research Council (EP/P022286/1)
Engineering and Physical Sciences Research Council (EP/K025791/1)