Flow and Temperature Characteristics of a 15° Backward-Inclined Jet Flame in Crossflow

The flow and flame characteristics of a 15° backward-inclined jet flame in crossflow were investigated in a wind tunnel. The flow structures, flame behaviors, and temperature fields were measured. The jet-to-crossflow momentum flux ratio was less than 7.0. The flow patterns were investigated using photography and Mie-scattering techniques. Meanwhile, the velocity fields were observed using particle image velocimetry techniques, whereas the flame behaviors were studied using photographic techniques. The flame temperatures were probed using a fine-wire R-type thermocouple. Three flame modes were identified: crossflow dominated flames, which were characterized by a blue flame connected to a down-washed yellow recirculation flame; transitional flames identified by a yellow recirculation flame and an elongated yellow tail flame; and detached jet dominated flames denoted by a blue flame base connected to a yellow tail flame. The effect of the flow characteristics on the combustion performance in different flame regimes is presented and discussed. The upwind shear layer of the bent jet exhibited different coherent structures as the jet-to-crossflow momentum flux ratio increased. The transitional flames and detached jet dominated flames presented a double peak temperature distribution in the symmetry plane at x/d = 60. The time-averaged velocity field of the crossflow dominated flames displayed a standing vortex in the wake region, whereas that of the detached jet dominated flames displayed a jet-wake vortex and a wake region source point.

[1]  Larry W. Kostiuk,et al.  The use of a closed-loop wind tunnel for measuring the combustion efficiency of flames in a cross flow , 1999 .

[2]  H. F. Sullivan,et al.  The Turbulent Hydrogen Diffusion Flame in a Cross-wind , 1975 .

[3]  G. Kalghatgi.  Blow-Out Stability of Gaseous Jet Diffusion Flames Part II: Effect of Cross Wind , 1981 .

[4]  Ernest F. Hasselbrink,et al.  Transverse jets and jet flames. Part 1. Scaling laws for strong transverse jets , 2001, Journal of Fluid Mechanics.

[5]  Mingchun Luo,et al.  Effects of Radiation on Temperature Measurement in a Fire Environment , 1997 .

[6]  Donghee Han,et al.  Simultaneous measurements of velocity and CH distribution. Part II: deflected jet flames , 2003 .

[7]  Rong Fung Huang,et al.  An experimental study of elevated round jets deflected in a crosswind , 2002 .

[8]  A. Karagozian,et al.  The flame structure and vorticity generated by a chemically reacting transverse jet , 1986 .

[9]  R. Huang,et al.  Characteristic modes and evolution processes of shear-layer vortices in an elevated transverse jet , 2005 .

[10]  M. Delichatsios,et al.  Blow-out limits of nonpremixed turbulent jet flames in a cross flow at atmospheric and sub-atmospheric pressures , 2015 .

[11]  Larry W. Kostiuk,et al.  Efficiencies of low-momentum jet diffusion flames in crosswinds , 2000 .

[12]  S. Gollahalli,et al.  Burner Wake Stabilized Gas Jet Flames in Cross-Flow , 1995 .

[13]  G. Kalghatgi.  Blow-Out Stability of Gaseous Jet Diffusion Flames: Part III - Effect of Burner Orientation to Wind Direction , 1982 .

[14]  R. Huang,et al.  Effects of jet pulsation intensity on a wake-stabilized non-premixed jet flame in crossflow , 2016 .

[15]  J. Westerweel.  Fundamentals of digital particle image velocimetry , 1997 .

[16]  T. A. Brzustowski,et al.  An experimental and theoretical study of the turbulent diffusion flame in cross-flow , 1979 .

[17]  R. Huang,et al.  Non-Premixed Burner-Attached Jet Flames in Crossflow Pulsed at Resonance Frequency , 2017 .

[18]  W. Rodi,et al.  Experimental investigation of jets in a crossflow , 1982, Journal of Fluid Mechanics.

[19]  Rong Fung Huang,et al.  The stability and visualized flame and flow structures of a combusting jet in cross flow , 1994 .

[20]  Rong Fung Huang,et al.  Characteristic flow modes of wake-stabilized jet flames in a transverse air stream , 1999 .

[21]  R. Huang,et al.  Coherent structure in a combusting jet in crossflow , 1994 .

[22]  Donghee Han,et al.  Stabilization in turbulent lifted deflected-jet flames , 2002 .

[23]  Ray W. Grout,et al.  Mechanisms of Flame Stabilization and Blowout in a Reacting Turbulent Hydrogen Jet in Cross-Flow , 2012 .

[24]  D. Wilson,et al.  A FUEL STRIPPING MECHANISM FOR WAKE-STABILIZED JET DIFFUSION FLAMES IN CROSSFLOW , 2001 .

[25]  Richard D. Keane,et al.  Theory of cross-correlation analysis of PIV images , 1992 .