Gibson scaling and related properties of flame-surface geometry in turbulent premixed combustion are demonstrated using a novel computational model, Deterministic Turbulent Mixing (DTM). In DTM, turbulent advection is represented by a sequence of maps applied to the computational domain. The structure of the mapping sequence incorporates pertinent scaling properties of the turbulent cascade. He...

The LES method is an attractive approach for the simulation of turbulent jet flames. In this method, the effects of large scale structures controlling the mixing process are resolved while small-scale effects such as the leading-edge flames involved in the flame base dynamics are accounted for by the subgrid-scale models. The LES approach is examined in this study with a particular emphasis on ...

The Fourth International Workshop on Measurement and Computation of Turbulent Nonpremixed Flames (TNF4) was hosted by the Darmstadt University of Technology and was attended by 87 researchers from 10 countries. The main topics of discussion included: results for the piloted CH4/air jet flames D, E, and F progress on calculations of bluff-body stabilized flames progress on LES for combustion exp...

0010-2180/$ see front matter 2009 The Combust doi:10.1016/j.combustflame.2009.11.009 * Corresponding author. Present address: CFD Rese AL 35805, United States. Fax: +1 256 726 4806. E-mail addresses: [email protected] (R.S. Mehta), dch [email protected] (M.F. Modest). 1 Present address: Department of Mechanical Engine Merced, CA 95348, United States. A comprehensive model for luminous turbulent ...

Since a large number of physical variables are involved in the combustion process occurring in complex swirl stabilized combustors, simple systems (burner stabilized laminar flat flames) were initially studied (see chapters 5 and 6). Having understood the dynamics of laminar flat flames and developed methodologies to build reduced order flame dynamic models, the technique developed to measure t...

A recent numerical study of turbulence-flame interactions in lean premixed hydrogen, where the Lewis number was approximately 0.36, observed that flames at different equivalence ratios presented significantly different behavior despite having the same Karlovitz and Damköhler numbers. This differing behavior is due to the thermodiffusively-unstable nature of low Lewis number flames. In more than...

Uncontrolled fires produce flames where the initial momentum of the fuel is low compared with the momentum produced by buoyancy. The heights of such flames with wood as the fuel are examined and discussed in terms of both a dimensional analysis and the entrainment of air into the turbulent flame. They are then compared with other experiments on the flow of hot gases. Some recent experiments on ...

An extension to the level set flamelet model of Peters [1] for premixed turbulent combustion that takes the effects of cold ambient air entrainment into account is presented. The model is valid in the flamelet regime, where the reaction zone thickness is smaller than the Kolmogorov length scale. The inner structure of the instantaneous flame front is taken into account by a presumed pdf approac...

This paper presents a brief overview of our INCITE 2007 project on the direct numerical simulation of nonpremixed flames subjected to turbulent flows and water spray evaporation. The simulation is a culmination of our recent developments in advanced physical submodels associated with radiative heat transfer and Lagrangian spray dynamics. One of the main objectives is to identify and verify a un...