简单剪切流动中液滴断裂机理

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简单剪切流动中液滴断裂机理

林长志; 郭烈锦

State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China

收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2007-02-28 发布日期:2007-02-28
通讯作者: 林长志

Experimental study of drop deformation and breakup in simple shear flows

LIN Changzhi; GUO Liejin

State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China

Received:1900-01-01 Revised:1900-01-01 Online:2007-02-28 Published:2007-02-28
Contact: LIN Changzhi

摘要/Abstract

摘要： The experimental results of the deformation and breakup of a single drop immersed in a Newtonian liquid and subjected to a constant shear rate which generated by counter rotating Couette apparatus were presented in this paper. From experimental observations, the breakup occurred by three mechanisms, namely, necking, end pinching, and capillary instability. Quantitative results for the deformation and breakup of drop are presented. The maximum diameter and Sauter mean diameter of daughter drops and capillary thread radius are linearly related to the inverse shear rate and independent of the initial drop size, the dimensionless wavelength which is the wavelength divided by the thread width at breakup is independent of the shear rate and initial drop size, and the deformation of threads follows a pseudo-affine deformation for Cai/Cac larger than 2.

关键词: drop;deformation;breakup;Couette shear flow

Abstract: The experimental results of the deformation and breakup of a single drop immersed in a Newtonian liquid and subjected to a constant shear rate which generated by counter rotating Couette apparatus were presented in this paper. From experimental observations, the breakup occurred by three mechanisms, namely, necking, end pinching, and capillary instability. Quantitative results for the deformation and breakup of drop are presented. The maximum diameter and Sauter mean diameter of daughter drops and capillary thread radius are linearly related to the inverse shear rate and independent of the initial drop size, the dimensionless wavelength which is the wavelength divided by the thread width at breakup is independent of the shear rate and initial drop size, and the deformation of threads follows a pseudo-affine deformation for Cai/Cac larger than 2.

Key words: drop, deformation, breakup, Couette shear flow

林长志, 郭烈锦. 简单剪切流动中液滴断裂机理[J]. , DOI: .

LIN ,Changzhi, GUO ,Liejin. Experimental study of drop deformation and breakup in simple shear flows[J]. , DOI: .

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