低频声波作用下微液滴沉降实验研究

Experimental Study on Micro-Droplet Sedimentation Under the Action of Low-Frequency Acoustic Wave

声凝并被认为是一种潜在的消雾、大气凝胶去除技术.本文设计室内实验,研究了微液滴在高强度平面声场中的粒径动态响应及声致凝聚行为.结果表明,声波频率显著影响微液滴的特征粒径,对于特征粒径D90,即小于该粒径的体积占总体积的90%,最佳声波频率为60Hz,粒径响应平衡时间为45s.当声波频率为100Hz,平均声压级为124dB,声场行程为1.5m,雾化通量为24g/min时,微液滴特征粒径D90在声波作用后呈现出稳定增大趋势,平均增大29μm.声波频率、声压级、声场行程、雾化通量是影响微液滴特征粒径的关键因素,除声波频率外,均与特征粒径增量呈线性正相关关系.

Acoustic agglomeration is concerned as a potential technique to defogging and aerosol removal.A laboratory experiment is designed to study the dynamic response of particle size and the behavior of acoustic agglomeration of micro-droplet under the action of high-intensity plane sound field.The results show that the frequency of sound wave significantly affects the microdroplet characteristic diameter,for the characteristic diameter D90,namely less than the microdroplet volume of this diameter accounts for 90%of the total volume,the optimal frequency is 60 Hz,and the particle size response equilibrium time is 45 s.when the average sound pressure level of 124 dB,the acoustic field route of 1.5 m and the atomization flux of 24 g/min,the characteristic diameter D90 of microdroplet shows a stable increasing trend under the action of acoustic wave,with an average increase of 29μm.Acoustic frequency,intensity,propagating distance,and atomization flux are the key factors affecting the characteristic size of microdroplet in the acoustic field.The above parameters are linearly positively correlated with the feature increment of droplet size,except for the acoustic frequency.