Research on pneumatic water mist flow field based on PIV

doi:10.16265/j.cnki.issn1003-3033.2020.07.018

Abstract

Abstract: In order to explore morphological changes of pneumatic water mist flow field under different gas pressures, GLR of pneumatic two-fluid water mist nozzles were measured by using mass flow controllers and PIV technology. Then, features of flow field were analyzed under gas driving pressure between 0.1-0.3 MPa. The results show that under nitrogen pressure of 0.1-0.4 MPa, dimensionless GLR value of water mist nozzles presents a linear growth relationship with nitrogen pressure, and GLR exerts impacts on characteristics of two-phase flow inside the nozzle, liquid breakdown mechanism, droplet dynamics and final droplet size distribution. When gas pressure increases from 0.1 MPa to 0.3 MPa, average atomization cone angle shrinks from 55.02° to 27°, and main velocity range of water mist particles rises from 0-5 m/s to 0-12 m/s. Average vorticity at vortex increases from 166.502 81 s^-1 to 671.191 26 s^-1, and vortex structure of particle air mass shows counterclockwise rotation.

Key words: particle image velocimetry (PIV), pneumatic water mist, flow field, gas-liquid mass flow ratio (GLR), atomization cone angle, vorticity

CLC Number:

X932

LIU Chenghui, CHEN Xianfeng, ZHANG Wei, XU Lexian, ZHAO Qi, HUANG Chuyuan. Research on pneumatic water mist flow field based on PIV[J]. China Safety Science Journal, 2020, 30(7): 120-126.

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