An Experimental Study on the Lift-off Behavior of Tone-Excited Propane Non-premixed Jet Flames

An experimental study conducted to determine the effects of lifting the flame base off the burner rim on the differences between the flame characteristics of diffusion flames from circular and elliptic burners is presented. The in-flame profiles of temperature, concentrations of fuel and combustion product species, and the mean and fluctuating components of axial velocity are presented. This study has shown that the effects of burner geometry in turbulent lifted flames are considerable only in the near-burner region. In the midflame and far-burner regions, the effects traceable to burner geometry are much weaker, contrary to those observed in the attached flame configuration. The observations are attributed to the turbulence and additional air entrainment into the jet prior to the flame base accompanying the lift-off process, which mitigate the effects of burner geometry.

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Experimental study of vorticity-strain rate interaction in turbulent partially premixed jet flames using tomographic particle image velocimetry

Physics of Fluids ◽

10.1063/1.4941528 ◽

2016 ◽

Vol 28 (2) ◽

pp. 025109 ◽

Cited By ~ 14

Author(s):

Bruno Coriton ◽

Jonathan H. Frank

Keyword(s):

Experimental Study ◽

Particle Image Velocimetry ◽

Strain Rate ◽

Particle Image ◽

Tomographic Particle Image Velocimetry ◽

Jet Flames ◽

Image Velocimetry ◽

Partially Premixed ◽

Rate Interaction

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Lift-off heights in underexpanded natural gas jet flames

Symposium (International) on Combustion ◽

10.1016/s0082-0784(89)80092-x ◽

1989 ◽

Vol 22 (1) ◽

pp. 825-831 ◽

Cited By ~ 6

Author(s):

A.D. Birch ◽

G.K. Hargrave

Keyword(s):

Natural Gas ◽

Gas Jet ◽

Jet Flames ◽

Lift Off

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Experimental Study Of Short Hole Film-Cooling

10.32920/ryerson.14665287.v1 ◽

2021 ◽

Author(s):

Mohammed A. Gandhi

Keyword(s):

Experimental Study ◽

Wind Tunnel ◽

Film Cooling ◽

Double Row ◽

Cooling Effectiveness ◽

Film Cooling Effectiveness ◽

Single Row ◽

Blowing Ratio ◽

Lift Off ◽

Low Speed Wind Tunnel

An experimental study was conducted to investigate the film cooling effectiveness of a few configurations of short injection holes: single row, double row and both of the preceding cases with an upstream ramp placed at two different locations. In order to perform the above study, a wind-tunnel facility was assembled to facilitate in the successful culmination of the experiments. The focus of the study was to determine the cooling provided by the short injection holes at a variety of blowing ratios and whether adding an extra row of holes, upstream of the first row would make a difference. For the second part, a ramp was placed upstream of the single and double row configuration to help improve cooling . All of the experiments were performed in a low speed wind-tunnel with a mainstream velocity of 8 m/s and a turbulence insity of 3.3%. Higher blowing ratios were ineffective in improving film-cooling effectiveness due to jet lift-off. Two rows of holes increased the cooling effectiveness by 200%, when compared to single row configurations at the same blowing ratio without ramps. Upstream ramps provided significant improvement in the near hole region of the injection holes.

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Experimental Study Of Short Hole Film-Cooling

10.32920/ryerson.14665287 ◽

2021 ◽

Author(s):

Mohammed A. Gandhi

Keyword(s):

Experimental Study ◽

Wind Tunnel ◽

Film Cooling ◽

Double Row ◽

Cooling Effectiveness ◽

Film Cooling Effectiveness ◽

Single Row ◽

Blowing Ratio ◽

Lift Off ◽

Low Speed Wind Tunnel

An experimental study was conducted to investigate the film cooling effectiveness of a few configurations of short injection holes: single row, double row and both of the preceding cases with an upstream ramp placed at two different locations. In order to perform the above study, a wind-tunnel facility was assembled to facilitate in the successful culmination of the experiments. The focus of the study was to determine the cooling provided by the short injection holes at a variety of blowing ratios and whether adding an extra row of holes, upstream of the first row would make a difference. For the second part, a ramp was placed upstream of the single and double row configuration to help improve cooling . All of the experiments were performed in a low speed wind-tunnel with a mainstream velocity of 8 m/s and a turbulence insity of 3.3%. Higher blowing ratios were ineffective in improving film-cooling effectiveness due to jet lift-off. Two rows of holes increased the cooling effectiveness by 200%, when compared to single row configurations at the same blowing ratio without ramps. Upstream ramps provided significant improvement in the near hole region of the injection holes.

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Numerical and Experimental Study on Lift-Off Suppression Phenomenon of Subsonic Hydrogen Jet Diffusion Flame

2010 14th International Heat Transfer Conference, Volume 3 ◽

10.1115/ihtc14-22116 ◽

2010 ◽

Author(s):

Shuichi Torii

Keyword(s):

Experimental Study ◽

Diffusion Flame ◽

Fuel Injection ◽

Numerical Study ◽

Vacuum Pressure ◽

Jet Flame ◽

Injection Nozzle ◽

Circular Nozzle ◽

Lift Off

Experimental and numerical study is performed on subsonic hydrogen jet diffusion flame formed from the vertical circular nozzle. Emphasis is placed on the effect of the cavity height formed at the fuel injection nozzle tip on suppression of the flame lift-off. It is found that (i) an increase in the cavity height triggers and enhances a vacuum pressure, (ii) the air from the surroundings is transported naturally into the cavity to replenish the air entrained and consumed by the jet flame, and (iii) the vacuum pressure results in the mitigation of flame lift-off propensity.

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