双层桨搅拌釜气液两相流的混合效果研究
Study on the Mixing Effect of Gas-Liquid Flow in the Stirred Tank with Double Paddle
高晨育 1李强1
作者信息
摘要
针对双层桨搅拌釜,采用RNG k-ε湍流多相流模型进行模拟,研究了径向流平直式RT桨、轴向流斜叶式PB桨 3 种组合双层桨的气液两相流动混合特性.RT-RT双层桨在釜内形成几个比较对称、均匀的涡流,导致釜底进入的气相在桨叶中心附近的较低压区域富集;引入轴向流的PB-RT显著提高了两层桨叶间的液相流速,使得搅拌釜内整体的涡流都向气相进口方向移动,提高两层桨叶中间区域的局部气含率,比RT-RT双层桨的整体气含率略高,但搅拌功率下降 57%;而PB-PB双层桨具有最高的气含率,但搅拌功率比PB-RT高 49%.
Abstract
Aiming at the double-paddle stirred tank,having the RNG k-ε turbulent multiphase flow model adopted to investigate gas-liquid flow's mixing characteristics of such three combined double paddles as the radial-flow RT straight paddle and axial-flow PB oblique blade paddle was implemented.The result show that,the RT-RT double paddle brings about several symmetric and uniform vortexes in the stirred tank,which results in the gathering of the gas which entered the tank bottom in the lower pressure area near the center of the paddle.The axial flow brought in by the PB-RT significantly improves the liquid flow velocity between the two paddlers and makes the overall eddy flow in the stirred tank move to the inlet direction of the gas;in addition,improving the local gas holdup in the middle region of the two paddlers slightly and making it higher than the overall gas holdup of the RT-RT double paddlers will cause the stirring power re-duced by 57%.The PB-PB double paddle has the highest gas holdup,and its stirring power is 49%higher than that of PB-RT.
关键词
搅拌釜/气液两相流/双层桨/平直桨/斜叶桨Key words
stirred tank/gas-fluid flow/double paddle/straight paddle/oblique propeller引用本文复制引用
出版年
2024
NETL
NSTL
万方数据