Triple flame structure and dynamics at the stabilization point of a lifted jet diffusion flame

Conference · Sun Mar 01 04:00:00 EST 1998

OSTI ID:671896

Najm, H N; Milne, R B ^[1]; Devine, K D; Kempka, S N ^[2]

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1. Sandia National Labs., Livermore, CA (United States)
2. Sandia National Labs., Albuquerque, NM (United States)

A coupled Lagrangian-Eulerian low-Mach-number numerical scheme is developed, using the vortex method for the momentum equations, and a finite difference approach with adaptive mesh refinement for the scalar conservation equations. The scheme is used to study the structure and dynamics of a forced lifted buoyant planar jet flame. Outer buoyant structures, driven by baroclinic vorticity generation, are observed. The flame base is found to stabilize in a region where flow velocities are sufficiently small to allow its existence. A triple flame is observed at the flame base, a result of premixing of fuel and oxidizer upstream of the ignition point. The structure and dynamics of the triple flame, and its modulation by jet vortex structures, are studied. The spatial extent of the triple flame is small, such that it fits wholly within the rounded flame base temperature field. The dilatation rate field outlines the edge of the hot fluid at the flame base. Neither the temperature field nor the dilatation rate field seem appropriate for experimental measurement of the triple flame in this flow.

• Research Organization: Sandia National Labs., Livermore, CA (United States)
• Sponsoring Organization: USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 671896
• Report Number(s): SAND--98-8464C; CONF-980804--; ON: DE98052513
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
COMBUSTION INSTABILITY
COMBUSTION KINETICS
FLAMES
FLOW RATE
FLUID MECHANICS
MATHEMATICAL MODELS
METHANE
MORPHOLOGY