Linear instability of the electrified free interface between two cylindrical shells of viscoelastic fluids through porous media

作     者：Magdy A. Sirwah 

作者机构：Department of Mathematics Faculty of Science Tanta University 

出 版 物：《Acta Mechanica Sinica》 (力学学报（英文版）)

年 卷 期：2012年第28卷第6期

页      面：1572-1589页

核心收录：

学科分类：080704[工学-流体机械及工程] 080103[工学-流体力学] 08[工学] 0807[工学-动力工程及工程热物理] 081402[工学-结构工程] 081304[工学-建筑技术科学] 0802[工学-机械工程] 0813[工学-建筑学] 0814[工学-土木工程] 0701[理学-数学] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

主　　题：Modified Darcy's law Oldroyd-B model Cap-illary stability flow Insoluble surfactant Surface charges Porous media 

摘      要：In this paper, we have discussed the linear stabil- ity analysis of the electrified surface separating two coaxial Oldroyd-B fluid layers confined between two impermeable rigid cylinders in the presence of both interfacial insoluble surfactant and surface charge through porous media. The case of long waves interfacial stability has been studied. The dispersion relation is solved numerically and hence the ef- fects of various parameters are illustrated graphically. Our results reveal that the influence of the physicochemical pa- rameterβ is to shrink the instability region of the surface and reduce the growth rate of the unstable normal modes. Such important effects of the surfactant on the shape of in- terfacial structures are more sensitive to the variation of the βcorresponding to non-Newtonian fluids-model compared with the Newtonian fluids model. In the case of long wave limit, it is demonstrated that increasing r, has a dual role in- fluence （de-stabilizing effects） depending on the viscosity of the core fluid. It has a destabilizing effect at the large values of the core fluid viscosity coefficient, while this role is ex- changed to a regularly stabilizing influence at small values of such coefficient.