气液两相环状流射流液膜的破碎与雾化特性实验研究

In the present work, the characteristics of the deformation, breakup and atomization of the liquid film of gas-liquid annular flow jet were experimentally investigated by using visualization technique. It is found that the breakup of the liquid film of the annular flow jet has the features of periodicity and discontinuity. The results also show that there exist three breakup modes for the annular liquid film under different flow conditions, namely the burst breakup mode, the two-section breakup mode and the annular bag breakup mode. The critical dynamic conditions for different breakup modes are clarified based on the experimental results. In the case of the two-section mode, the effects of the gas-to-liquid momentum flux ratio of the annular flow on the breakup lengths for both the forepart and the rear part of the jet liquid film are obtained and the dimensionless correlations for them are developed. Moreover, the breakup features of the liquid films in both parts of the jet and the size distribution of the atomized droplets are discussed. It is shown that as the gas-to-liquid momentum flux ratio of the annular flow jet increases, both the droplets coming from the liquid filaments produced by the breakup of the rear part liquid film and the node droplets generated from the forepart liquid film all become smaller, and the atomization performance of the jet become better.