Abstract A flamelet-based approach that accounts for turbulence-chemistry interaction has been formulated to simulate NOx formation in turbulent lean premixed combustion. In the simulations, the species NO is transported and solved with the chemical source term being modelled through its formation in flame fronts and its formation rate in post-flame regions. The flame-front NO and post-flame NO...

Three-dimensional direct numerical simulation of lean premixed hydrogen flames is used to explore the influence of species and thermal diffusion and viscosity on the flame structure and turbulent flame response. The leadingorder flame response is shown to be due to the global Lewis number with little influence from the other species. The previously-reported observation of decorrelation of fuel ...

We study the dynamics and properties of a turbulent flame, formed in the presence of subsonic, high-speed, homogeneous, isotropic Kolmogorov-type turbulence in an unconfined system. Direct numerical simulations are performed with Athena-RFX, a massively parallel, fully compressible, high-order, dimensionally unsplit, reactive-flow code. A simplified reaction-diffusion model represents a stoichi...

An experimental and theoretical investigation of free turbulent premixed flames propagating in isotropic turbulence at neutrally stable preferential diffusion conditions is described. Experiments were limited to the wrinkled thin laminar ftamelet regime and involved mixtures of hydrogen, air, and nitrogen ignited within a fan-stirred combustion chamber. Measurements included flame tomography fo...

The flame stability limit, which was involving the critical flow condition, lift off and blow out, could be affected by the burner geometry in the combustion system installation. Consequently a flame holder should be put in, to hold the flame as big as possible on a stable condition. The flame holder itself, is a device to hold the flame, whereas the flame holder could disturb the air and fuel ...

In this paper we study the behavior of a premixed turbulent methane flame in three dimensions using numerical simulation. The simulations are performed using an adaptive time-dependent low Mach number combustion algorithm based on a second-order projection formulation that conserves both species mass and total enthalpy. The species and enthalpy equations are treated using an operator-split appr...

The large range of time and length scales involved in type Ia supernovae (SN Ia) requires the use of flame models. As a prelude to exploring various options for flame models, we consider, in this paper, high-resolution three-dimensional simulations of the small-scale dynamics of nuclear flames in the supernova environment in which the details of the flame structure are fully resolved. The range...

Two combustion models for turbulent premixed combustion in the flamelet regime are developed for unsteady simulations. The first model is a convensional G equation flamelet model and the main issues discussed are the subgrid closure. The second model is based on the Linear-Eddy Model. Both models are used in simulation of turbulent stagnation point flames. The heat release and turbulence intens...

In previous studies, we examined turbulence-flame interactions in carbonburning thermonuclear flames in Type Ia supernovae. In this study, we consider turbulence-flame interactions in the trailing oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the ox...