应用2D-PIV技术的三维湍流流场测量方法  

Measurement of 3D turbulent flow field based on 2D-PIV technique

作　　者：吴利芸 李坤[2] WU Liyun;LI Kun(Department of Mechanical Engineering,Taiyuan Institute of Technology,Taiyuan 030008,China;Shanxi Key Laboratory of Signal Capturing and Processing,North University of China,Taiyuan 030051,China)

机构地区：[1]太原工业学院机械工程系,山西太原030008 [2]中北大学信息探测与处理山西省重点实验室,山西太原030051

出　　处：《中国测试》2025年第3期59-67,共9页China Measurement & Test

基　　金：太原工业学院引进人才科研资助项目(2022LJ024)。

摘　　要：机械搅拌釜广泛应用于各种工业领域的混合操作,然而其内部三维流场常被假设为宏观对称的二维流场,且实验测量仅局限于单个垂直平面,未考虑搅拌方向不同位置处局部流场的细节变化。针对这一问题,提出一种在不同垂直平面多次进行2D PIV测量的方法,旨在解析速度场和湍流动能(TKE)在三维空间内的分布情况。随着PIV测量平面旋转,首次发现湍流流场在旋转方向上逐渐变化的重要细节。在靠近挡板的位置(5°和85°平面),主要大漩涡尺寸较大,且其中心点接近叶轮;然而在远离挡板的位置(25°、45°和65°平面),主要大漩涡尺寸较小,且其中心点接近壁面。挡板前(85°平面)的速度幅值明显大于挡板后(5°平面)的速度场,这是由于挡板的刚性阻挡作用改变流体流动方向。在各测量平面上,TKE主要分布在大漩涡流动区域,在搅拌釜顶部和底部几乎为零,且最高TKE值通常位于大漩涡的底部。该结果可为湍流扩散系数、耗散率等参数的测量计算和湍流数值仿真的新模型验证等提供一定的支撑。Mechanical stirred vessels are widely used in various industrial mixing operations.However,their internal three-dimensional flow field is often assumed to be a macroscopic symmetric 2D flow,and experimental measurements are often limited to a single vertical plane,without considering the detailed changes in local flow fields at different positions in the stirring direction.In this paper,multiple 2D PIV measurements on different vertical planes are proposed to resolve the velocity field and turbulent kinetic energy distribution in 3D space.With the rotation of PIV measurement plane,for the first time,important details of turbulent flow fields are found.In the PIV planes close to the baffle(5°and 85°planes),the main large vortex has a larger size and its center point is close to the impeller;However,in the PIV planes far away from the baffle(25°,45°,and 65°planes),the main vortex has a smaller size and its center point is close to the wall surface.The velocity amplitude in the plane on windward side of the baffle(85°plane)is significantly larger than that on leeward side of the baffle(5°plane),which is due to the blocking effect of the baffle.In each PIV plane,TKE is mainly distributed in the large vortex flow area,almost zero at the top and bottom of the stirred vessels,and the highest TKE value is usually located at the bottom of the large vortex.Results could provide a certain support for the measurement of turbulent diffusion coefficient and dissipation rate,as well as for the validation of new turbulent models.

关 键 词：搅拌釜 三维流场 湍流动能 粒子图像测速技术 

分 类 号：TB9[一般工业技术—计量学] TH814[机械工程—测试计量技术及仪器]