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Show 1. Introduction The key to successful burner design lies in controlling the near-burner aerodynamics of the combustion air to produce a' ,match between the flame reaction rates and the imposed velocties. It is well known that the application of swirl to the combustion air stream to create a recirculation zone 'in front of the burner is an effective ' means of flame stabilization and allows an increase in the range of burner loads without reducing flame stability. The recirculating flutd generates regions of high turbulence in the shear layer between the forward and the reverse flow, resulting in faster mix~ng of the combustion air with the ,injected fuel. The flow pattern and turbulence characteristics developed by swirling flows can be affected by swirl profile, swirl level, diameter, and burner bluff body blockage ratio [1-5]. The main objectives of this study are to improve the understanding of the aerodynamics characteristics of the i ndustri a 1 burner . ... S i mu 1 taneous-.. _measurements-. of _·the axi a 1 and azimuthal velocities by use of back-scattered, two-component isothermal and quantitative intensity of provided. laser-Doppler anemometer have been made in an nonreacting expanding-swirling flow. Some informations, the central such as the size, shape and recirculation zone, were also 2. Experiment A schematic diagram of the wind tunnel configuration is shown in Fig.l. A swirling nonreacting flow, with a inlet swirl number So of 2.0, is generated by an axial vane swirl |