金洁,范赢
JIN Jie,FAN Ying

• 1:上海大学上海市力学在能源工程中的应用重点实验室上海市应用数学与力学研究所力学与工程科学学院
• 2:兰州理工大学能源与动力工程科学学院
• 3:甘肃省流体机械及系统重点实验室
• 4:河北工业大学过程装备与控制工程系

摘要(Abstract)：

为了解磁力搅拌过程湍流特性,对其开展了激光粒子图像测速(PIV)试验,并进行了本征正交分解(POD)分析。分析表明,在测量平面转子外部区域,除平均流动,含能量较高的流动结构为循环剪切流和转子旋转的尾涡结构。在搅拌槽底部具有较高的旋涡强度,有利于固体颗粒悬浮。流体与转子之间的流-固耦合作用使转子产生振荡,随转速升高,系统稳定性下降,平均流动含能降低,小尺度结构含能增加,涡流扩散增强,有利于混合和反应进行。
In order to understand the turbulent flow characteristics of the magnetic stirring process,the Laser Particle Image Velocimetry(PIV) experiment is carried out on them,and Proper Orthogonal Decomposition(POD) method is used to analyze them.As demonstrated by the results,in the outer region of the planar rotor,the flow structures with higher energy are the cyclic shear flow and wake vortex structure of rotor rotation.The swirling strength at the bottom of the stirring tank is higher,which is conducive to the suspension of solid particles except the average flow.The coupling between the fluid and the rotor causes the rotor to oscillate.With the increase of rotational speed,the system stability decreases,the average flow energy content decreases,the energy content of small-scale structure increases,and the vortex expansion is enhanced,which are conducive to progress of mixing and reaction.

关键词(KeyWords)： 磁力搅拌;湍流特性;PIV测量;POD分析
magnetic stirrer;turbulence characteristics;PIV measurement;POD analysis

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金项目(11572357)

作者(Author): 金洁,范赢
JIN Jie,FAN Ying

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