To promote the mix of air and pulverized coal

and improve the combustion efficiency and control the emissions

vorticity distribution in burner zone of tangentially fired boiler was discussed.Three typical velocity and vorticity fields in horizontal planes was obtained

by measuring aerodynamic field in burner zone of the cold tangential firing boiler model using Particle Imaging Velocimetry sytem(PIV).Results indicate that

ring-shaped large vorticity area in the center of the furnace is the main combustion area where the pulverized coal mixes up with the air.The reversed vorticity in the furnace corner can easily cause slagging on the wall in secondary recirculation area.