The objective of this paper is to discuss the dynamical instability in the context of Newtonian and post Newtonian regimes. For this purpose, we consider non-viscous heat conducting charged isotropic fluid as a collapsing matter with cylindrical symmetry. Darmois junction conditions are formulated. The perturbation scheme is applied to investigate the influence of dissipation and electromagneti...

In this paper, the unsteady flow of non-Newtonian fluid through a porous medium when an external magnetic field is applied is investigated. The non linear equation of motion is transformed to a similarity differential equation which is solved using the method of successive approximations. The rheological effects are shown and discussed on the velocity profile in terms of rheological parameter o...

An analysis is made to see the influences of Hall current on the flow of a Burgers’ fluid. The velocity field corresponding to flow in a pipe is determined. The closed form analytical solutions for several Newtonian and non-Newtonian fluid models can be obtained from the present analysis as the limiting cases. MIRAMARE – TRIESTE December 2005 Corresponding author: mkhan−[email protected] Junior Asso...

In this paper heat transfer of non-Newtonian fluid flow in an axisymmetric channel with porous wall is analyzed. Variational Iteration Method is used to get complete analytic solution for velocity and temperature profiles. Results show an acceptable agreement between this method results and numerical solution.Also the effects of different parameters are discussed through graphs. It can be found...

The mirror fluid method is proposed for simulating viscous tubular flow of a Newtonian or non-Newtonian fluid past an irregular solid obstacle using a simple finite difference method for discretization. Suitable flow parameters in the solid domain are assigned by a mirror relation to ensure the surface segment is subjected to zero net shear and normal forces and the boundary conditions are enfo...

The Saffman-Taylor viscous fingering problem is investigated for the displacement of a non-Newtonian fluid by a Newtonian one in a radial Hele-Shaw cell. We execute a mode-coupling approach to the problem and examine the morphology of the fluid-fluid interface in the weak shear limit. A differential equation describing the early nonlinear evolution of the interface modes is derived in detail. O...

The entropy generation analysis of non-Newtonian fluid in rotational flow between two concentric cylinders is examined when the outer cylinder is fixed and the inner cylinder is revolved with a constant angular speed. The viscosity of non-Newtonian fluid is considered at the same time interdependent on temperature and shear rate. The Nahme law and Carreau equation are used to modeling dependenc...

We study the linear theory of perturbations in a Friedmann-Robertson-Walker universe with a cosmological constant. We obtain the equations for the evolution of the perturbations in the fully relativistic case, for which we analyze the single-fluid and the two-fluid cases. We obtain solutions to these equations in appropriate limits. We also study the Newtonian approximation. We find that for a ...