摘要
运用激光诱导荧光(PLIF)技术和大涡模拟方法对T型反应器内的流动特性进行了研究。发现随着Reynolds数(Re)的增大,T型反应器中依次出现分离流(Re<120)、稳定吞噬流(120≤Re<190)、非稳态吞噬流(190≤Re≤300)、非稳态对称流(Re>300)四种流动模式。通过大涡模拟重点考察了非稳态吞噬流的振荡特性。结果表明,在非稳态吞噬流型下,T型反应器内撞击面上会周期性地出现旋涡合并现象,合并的涡向下传递,产生自持振荡。此时撞击区的压力、速度和涡量也发生周期性变化,且变化周期与旋涡合并周期相同,这种振荡是由速度和压力的周期性转换引起的。
Flow regimes in the T-jets reactor were studied by planar laser induced fluorescence(PLIF)technique and large-eddy simulation(LES).It was found that four different flow regimes,the separated flow(Re<120),steady engulfment flow(120≤Re<190),unsteady engulfment flow(190≤Re≤300)and unsteady symmetric flow(Re>300)displayed in turns with the increase of Reynolds number.In particular,the characteristics of unsteady engulfment regime were investigated by LES.The results showed that eddies periodically merged in the impingement plan and the subsequent merged eddies passed through the chamber which caused self-sustained oscillation in the reactor.The pressure,velocity and vorticity in the impact zone also varied periodically,and the periods were consistent with that of eddy merging in unsteady engulfment regime.This oscillation of eddy merging and propagation is caused by the periodic variation of velocity and pressure in the impingement plane.
作者
许鑫磊
严嘉玮
张巍
李伟锋
张经纬
刘海峰
王辅臣
XU Xinlei;YAN Jiawei;ZHANG Wei;LI Weifeng;ZHANG Jingwei;LIU Haifeng;WANG Fuchen(Shanghai Gas Engineering Technology Research Center,Coal Gasification and Energy Chemical Engineering Key Laboratory of Ministry of Education,East China University of Science and Technology,Shanghai200237,China)
出处
《化工学报》
EI
CAS
CSCD
北大核心
2018年第12期5073-5080,共8页
CIESC Journal
基金
国家自然科学基金项目(21776072).
关键词
T型反应器
吞噬流
振荡
PLIF
大涡模拟
T-jets reactor
engulfment flow
oscillation
PLIF
large-eddy simulation
