Convenient Laser Diagnostics for Aerodynamic and Chemical Study of Axisymetric Non Premixed Bluff-Body Burner Flames
This paper presents an experimental investigation of a turbulent, non premixed, methane/air flame, produced by an axisymetric Bluff-Body burner. Only a few experimental data exists on time and spatially resolved fuel concentration and velocity fields on such reacting flows, despite their interest for a better understanding of combustion processes, modelling and numerical calculations in turbulent combustion.
The aim of this work is to provide these experimental data by using instantaneous, multiple point and spatially resolved measurements of methane concentration images by planar Mie scattering technique, and instantaneous velocity fields by cross-correlated Particle Image Velocimetry (PIV).
Results of methane concentration imaging using several tracer particles are compared to those obtained elsewhere from probe measurements. The Teflon marker is revealed to be the more efficient methane tracer in flow as it is capable to follow the aerodynamic flow fluctuations and to characterize the zones corresponding to CH4 consumption in the flame by identifying the mean identical decomposition temperature of CH4 molecules and Teflon particles. In this work we show that Mie scattering on Teflon particles is an accurate tracer in both reactive and non reactive flows as it gives information on methane concentration and flame structure.
The PIV vector fields are related to that previously measured using Laser Doppler Velocimetry. Analysis of the fluctuating velocity components in the PIV measurements reveals differences with LDV results which are mainly caused by the limited spatial resolution of the PIV method. The exploitation of PIV specific information, i.e. the spatial correlation of measurements, makes it possible to quantitatively study the coherent structures present in the flow.
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- Gray C, “The evolution of Particle Image Velocimetry”, IMechE Optical Methods and Data Processing in Heat and Fluid flow. Londres, pp 19–35, 1992.Google Scholar
- Lecordier B., Mouqallid M., Vottier S., Rouland E., Allano D., Trinité M., “CCD recording method for cross-correlation PIV development in unstationnary high speed flow”, 7th International Symposium on Applications of Laser Techniques to Fluid Mechanics. Lisbon, 1994.Google Scholar
- Mokaddem K, Perrin M. Y., Rolon J. C., Perrin M., Levinsky H., “Flame Front Visualization by C2 Spontaneous Emission and OH LIF in Axisymmetric Laminar Methane Air Premixed Flames”, 7th International Symposium on Application of Laser Techniques to Fluid Mechanics. Lisbon, 1994.Google Scholar
- Namazian M., Kelly J. T., Scheffer R. W., “Near Field Instantaneous Flame and Fuel Concentration Structure”, 22th (International) Symposium on Combustion/The Combustion Institute, pp 627–634, 1988.Google Scholar
- Namazian M., Kelly J. T., Scheffer R. W., Perrin M., “Effects of Confinement and Bluff-body Burner Recirculation Zone and Flame Stability”, IGRC. Cannes, 1995.Google Scholar
- Neveu F., Corbin F., Perrin M., Trinité M., “Simultaneous velocity and temperature measurements in turbulent flames obtained by coupling LDV and numerically compensated finewire thermocouple signals”, 7th International Symposium on Application of Laser Techniques to Fluid Mechanics. Lisbon, 1994.Google Scholar
- Perrin M., Namazian M., Kelly J., Scheffer R.W., “Effect of confinement and blocage ratio on non- premixed turbulent bluff-body burner flames”, 23th International) Symposium on Combustion/The Combustion Institute. Orléans, 1990.Google Scholar
- Perrin M., “Mesures de Conditions Aerodynamiques Initiales dans un Brûleur Bluff Body”, GDF Internal Report, Ref: M. CERSTA-Bcn N° 931060, 1993.Google Scholar
- Prwzeswa M., Albert S., “Mesures de Concentration de méthane dans un Brûleur Bluff Body “, GDF Internai Report, Ref: M. CERSTA-Bcn N° 931000, 1991.Google Scholar
- Rouland E., “Etude et développement de la technique de vélocimétrie par intercorrélation d´images de particules et application aux écoulements en tunnel hydrodynamique”, Thèse Rouen, 1994.Google Scholar
- Trinité M., “La vélocimétrie par Intercorrélation d´Images de Particules, Séminaire Européen, Le laser outil de Diagnostic en Milieu Industriel, GDF, La Plaine Saint Denis, 1993.Google Scholar