基于粒子图像测速(PIV)技术的圆盘桨搅拌槽湍流动能耗散率研究  

Particle image velocimetry(PIV)⁃based study of the turbulent kinetic energy dissipation rates in a disc impeller stirred tank

作　　者：胡帅 王瀚彬 毕丰雷 李隽森 贺来宾 HU Shuai;WANG HanBin;BI FengLei;LI JunSen;HE LaiBin(Sinopec Shanghai Research Institute of Petrochemical Technology Co.,Ltd.,Shanghai 201208,China)

机构地区：[1]中石化(上海)石油化工研究院有限公司,上海201208

出　　处：《北京化工大学学报（自然科学版）》2024年第5期39-45,共7页Journal of Beijing University of Chemical Technology(Natural Science Edition)

摘　　要：在边长L为220 mm的方形搅拌槽内,采用高解析率的二维粒子图像测速(PIV)技术在搅拌雷诺数Re=1300下对圆盘桨形成的流场进行研究,得到Kolmogorov尺度下的高解析流场。基于流场数据和各向同性假设得到湍流动能分布,并比较了直接定义法和大涡PIV法计算的湍流动能耗散率。结果表明:当离底高度C=0.15L时,圆盘桨的流型呈现出独特的单循环流型,流体主要旋涡为单旋涡结构;搅拌槽内湍流动能的最大值出现在桨叶排出流的末端;在Kolmogorov空间解析尺度下直接定义法计算得到的湍流动能耗散率大于大涡PIV法,并且湍流动能耗散率的峰值位于桨叶端和排出流区域。直接数值模拟的验证结果表明,这两种计算方法中使用的各向同性假设是合理的。High-resolution two-dimensional particle image velocimetry(PIV)has been used to study the flow field formed by a disc impeller with a stirring Reynolds number Re=1300 in a square stirred tank with a side length L of 220 mm,and the high-resolution flow field at the Kolmogorov scale was obtained.Based on the flow field data and the isotropic assumption,the turbulent kinetic energy distribution was obtained.The turbulent kinetic energy dissi-pation rates calculated by the direct definition method and the large eddy PIV method were compared.The results show that when the off-bottom height C=0.15L,the flow pattern of the disc impeller presents a unique single-cycle flow pattern,and the main vortex of the fluid is a single vortex structure.The maximum value of the turbulent kinetic energy in the stirred tank appears at the end of the blade discharge flow.At the Kolmogorov spatial analyti-cal scale,the turbulent kinetic energy dissipation rate calculated by the direct definition method is larger than that calculated by the large eddy PIV method,and the peak values of the turbulent kinetic energy dissipation rate are located at the blade end and the discharge flow region.The results of direct numerical simulation verify that the iso-tropic assumptions used in these two calculation methods are reasonable.

关 键 词：搅拌槽 粒子图像测速(PIV) Kolmogorov尺度 湍流动能耗散率 直接数值模拟 

分 类 号：TQ027.2[化学工程]