| This dissertation describes an experimental investigation on swirl spray flow field and swirl-stabilized flame based on effervescent atomization technic. As a new kind of gas-assist atomization, effervescent atomization is different from traditional air-assist atomization technic in principle and structure. A low mass flow rate effervescent atomization nozzle, with swirl combution equipment, has been constructed in this work. Diagnostic techniques include Laser Doppler anemometry to measure the axial, tangential and radial velocity components of the droplets under three different swirl numbers: S=0.7(vane angle=45 degree), S=1.2(vane angle=60 degree) and S=2.6(vane angle=75 degree).It is found that the spray angle increases due to the effect of swirl configuration, and an area of low axis-speed appears around the spray axis as well, and the horizon speed are characterized. In reacting flows, swirl air enhances the mixing-rate of air and fuel, the flame length decreased accordingly. The overall production of pollutants are linked to the swirl number. A decrease in pollutant emissions was observed when S=1.2. These results agree well with that of numerical simulation under similar conditions, and it is conformed that the air excess ratio and flow pattern must work together to improve the combust performance of effervescent atomization.
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