南京航空航天大学学报（英文版）2021，Vol.38Issue(6)：1003-1019,17.
旋涡环缝式雾化器气体流场对堵嘴现象的影响
Effects of Gas Flow Field on Clogging Phenomenon in Close-Coupled Vortical Loop Slit Gas Atomization
摘要
Abstract
In order to study the basic characteristics of gas flow field in the atomizing chamber near the nozzle outlet of the vortical loop slit atomizer and its influence mechanism on clogging phenomenon,the computational fluid dynamics(CFD)software Fluent is used to conduct a numerical simulation of the gas flow field in the atomizing chamber near the nozzle outlet of this atomizer under different annular slit widths,different atomization gas pressures and different protrusion lengths of the melt delivery tube.The results show that under atomization gas pressure p=4.5 MPa,the greater the annular slit width D,the lower the static temperature near the central hole outlet at the front end of the melt delivery tube,and the smaller the aspirating pressure at the front end of the melt delivery tube.These features can effectively prevent the occurrence of the clogging phenomenon of metallic melt.Under an annular slit width of D=1.2 mm,when the atomization gas pressure satisfies 1 MPa≤p≤2 MPa and increases gradually,the aspirating pressure at the front end of the melt delivery tube will decline rapidly.This can prevent the clogging phenomenon of metallic melt.However,when the atomization gas pressure p＞2 MPa,the greater the atomization gas pressure,the lower the static temperature near the central hole outlet at the front end of the melt delivery tube,and the greater the aspirating pressure at the front end of the melt delivery tube.Hence,the effect of preventing the solidification-induced clogging phenomenon of metallic melt is restricted.When atomization gas pressure is p=4.5 MPa and annular slit width is D=1.2 mm,the greater the protrusion length H of the melt delivery tube,and the smaller the aspirating pressure at its front end.The static temperature near the central hole that can be observed in its front end is approximate to effectively prevent the occurrence of clogging phenomenon of metallic melt.However,because of the small aspirating pressure,the metallic melt flows into the atomizing chamber from the central hole at the front end of the melt delivery tube at an increasing speed and the gas-melt ratio in the mass flow rate is reduced,which is not conducive to the improvement of atomization performance.关键词
旋涡环缝式雾化器/环缝宽度/雾化气体压强/导液管突出长度/气体流场/数值模拟Key words
vortical loop slit atomizer/annular slit width/atomization gas pressure/melt delivery tube protrusion length/gas flow field/numerical simulation分类
矿业与冶金引用本文复制引用
章敏,张召明,张彦奇,卢远靖,卢林..旋涡环缝式雾化器气体流场对堵嘴现象的影响[J].南京航空航天大学学报（英文版）,2021,38(6):1003-1019,17.基金项目
This work was supported by the Prior-ity Academic Program Development of Jiangsu Higher Edu-cation Institutions(PAPD)and the Simulation and Test of the Flow Field of Gas Atomization Nozzle(No.1001-KFA19184). （PAPD）
