Linear stability of plane creeping Couette flow for Burgers fluid  

作　　者：Kai-Xin Hu Jie Peng Ke-Qin Zhu 

机构地区：[1]Department of Engineering Mechanics, Tsinghua University

出　　处：《Acta Mechanica Sinica》2013年第1期12-23,共12页力学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (11172152)

摘　　要：It is well known that plane creeping Couette flow of UCM and Oldroy-B fluids are linearly stable. However, for Burges fluid, which includes UCM and Oldroyd-B fluids as special cases, unstable modes are detected in the present work. The wave speed, critical parameters and perturbation mode are studied for neutral waves. Energy analysis shows that the sustaining of perturbation energy in Poiseuille flow and Couette flow is completely different. At low Reynolds number limit, analytical solutions are obtained for simpli- fied perturbation equations. The essential difference between Burgers fluid and Oldroyd-B fluid is revealed to be the fact that neutral mode exists only in the former.It is well known that plane creeping Couette flow of UCM and Oldroy-B fluids are linearly stable. However, for Burges fluid, which includes UCM and Oldroyd-B fluids as special cases, unstable modes are detected in the present work. The wave speed, critical parameters and perturbation mode are studied for neutral waves. Energy analysis shows that the sustaining of perturbation energy in Poiseuille flow and Couette flow is completely different. At low Reynolds number limit, analytical solutions are obtained for simpli- fied perturbation equations. The essential difference between Burgers fluid and Oldroyd-B fluid is revealed to be the fact that neutral mode exists only in the former.

关 键 词：Linear stability theory Burgers fluid Creeping Couette flow - Elastic instability 

分 类 号：O35[理学—流体力学] TV131.21[理学—力学]