Hostname: page-component-76d6cb85b7-xh428 Total loading time: 0 Render date: 2026-07-18T19:51:45.130Z Has data issue: false hasContentIssue false

Turbulent flame–wall interaction: a direct numerical simulation study

Published online by Cambridge University Press:  19 August 2010

A. GRUBER*
Affiliation:
SINTEF Energy Research, 7465 Trondheim, Norway
R. SANKARAN
Affiliation:
National Center for Computational Science, Oak Ridge National Laboratory, TN 37831, USA
E. R. HAWKES
Affiliation:
School of Photovoltaic and Renewable Energy Engineering/School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney NSW 2052, Australia
J. H. CHEN
Affiliation:
Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94550, USA
*
Email address for correspondence: andrea.gruber@sintef.no

Abstract

A turbulent flame–wall interaction (FWI) configuration is studied using three-dimensional direct numerical simulation (DNS) and detailed chemical kinetics. The simulations are used to investigate the effects of the wall turbulent boundary layer (i) on the structure of a hydrogen–air premixed flame, (ii) on its near-wall propagation characteristics and (iii) on the spatial and temporal patterns of the convective wall heat flux. Results show that the local flame thickness and propagation speed vary between the core flow and the boundary layer, resulting in a regime change from flamelet near the channel centreline to a thickened flame at the wall. This finding has strong implications for the modelling of turbulent combustion using Reynolds-averaged Navier–Stokes or large-eddy simulation techniques. Moreover, the DNS results suggest that the near-wall coherent turbulent structures play an important role on the convective wall heat transfer by pushing the hot reactive zone towards the cold solid surface. At the wall, exothermic radical recombination reactions become important, and are responsible for approximately 70% of the overall heat release rate at the wall. Spectral analysis of the convective wall heat flux provides an unambiguous picture of its spatial and temporal patterns, previously unobserved, that is directly related to the spatial and temporal characteristic scalings of the coherent near-wall turbulent structures.

Information

Type
Papers
Copyright
Copyright © Cambridge University Press 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable