鼓泡塔内气液两相湍流实验研究  

Experimental investigation on gas-liquid two phase flow in a bubble column

作　　者：王树立[1] 赵会军[1] 

机构地区：[1]江苏工业学院机械系,江苏常州213016

出　　处：《化工科技》2004年第2期6-11,共6页Science & Technology in Chemical Industry

基　　金：国家自然科学基金资助项目 (2 9376 2 5 3)

摘　　要：介绍了研究鼓泡塔气液两相流的实验装置、实验方法。液相用激光多普勒测速技术 (LDV)测量 ,气相用粒子示踪测速技术 (PIV)测量。实验表明 ,轴向液相速度的径向分布呈塔中心峰值、壁面附近倒流形式 ,且与气相表观速度大小有关 ,当液相表观速度一定时 ,随气相表观速度增大而愈加陡峭 ,返混也剧烈。当表观液速与表观气速之比小于 19.6时 ,返混区总是存在 ,且返混区大小与高度有关。当表观液速与表观气速之比大于 19.6时 ,返混消失 ,含气率分布由塔中心峰值转向壁面峰值。径向液相速度既与气相表观速度有关又与位置高度有关 ,在塔底部呈现负值 ,这意味着向塔轴心方向流动。随着塔高增加 ,流动方向逐渐转变为向塔壁方向 。A bubble column of bubbly air/water two-phase flows was investigated in this paper, the liquid velocities and turbulent intensities were measured detailed by the laser doppler velocimeter (LDV) and the gas behaviour were measured detailed by particle image velocimeter(PIV).The influence of superficial liquid velocity and superficial gas velocity on the flow structure was investigated. The relationship formula of turbulent intensity and hold-up was obtained. The presence of the bubbles increased the level of turbulence in the flow. It was found that the bubbles tended to migrate toward the center of the column. The velocity profile at axial direction showed a peek in the center, and a backward flow near the wall when U_(SL)/U_(SG)<19.6. The radial velocity profile depended on the value of the superficial air velocity and height of the column,and flowed from the wall to the center at bottom of the column.The velocity profile at axial direction showed a peek near the wall when U_(SL)/U_(SG)>19.6. Measurements of liquid velocities in bubble columns, of different height and different superficial liquid velocities, gas velocities were obtained and discussed.

关 键 词：鼓泡塔 气液两相湍流 激光多普勒测速技术 LDV 粒子示踪测速技术 PIV 

分 类 号：TQ053.5[化学工程]