the value of the permeability in fluid flow through porous media is important for process investigation. in low reynolds number, the classic darcy’s law is suitable for simulation of fluid flow. in this paper, an experimental study for evaluation of preformed fiber permeability has been done. also, the deviations from the classical darcy law by experimental and numerical simulation of the navie...

in this paper, we present a comparative study between the modified variational iteration method (mvim) and a hybrid of fourier transform and variational iteration method (ftvim). the study outlines the efficiencyand convergence of the two methods. the analysis is illustrated by investigating four singular partial differential equations with variable coefficients. the solution of singular partia...

The motion of a viscous incompressible fluid flow in bounded domains with a smooth boundary can be described by the nonlinear Navier-Stokes equations. This description corresponds to the so-called Eulerian approach. We develop a new approximation method for the Navier-Stokes equations in both the stationary and the non-stationary case by a suitable coupling of the Eulerian and the Lagrangian re...

The anomalies in the anti-Stokes to Stokes intensity ratios in single-molecule surface-enhanced resonance Raman scattering were investigated. Brilliant green and crystal violet dyes were the molecular probes, and the experiments were carried out on an electrochemically activated Ag surface. The results allowed new insights into the origin of these anomalies and led to a new method to confirm th...

In recent years there has been lots of interest in the use of first-order system leastsquares method (FOSLS) for numerical approximations of elliptic partial differential equations, Stokes equations, elasticity and Navier-Stokes equations. In this paper we will provide a brief review of FOSLS around elliptic problems and Stokes equations. FOSLS is to find a minimization solution which minimizes...

Problem statement: We consider the numerical solvers for the linearized Navier-Stokes problem. Both the Stokes problem and Oseen problems are considered. Approach: We used the Mark and Cell (MAC) discretization method to discretize the Navier-Stokes equations. We used preconditioned Krylov subspace methods to solve the resulting linear systems. Results: Numerical experimental results are perfor...

A two levels finite element iterative method based on a pressure projection is proposed and analyzed for the transient Navier–Stokes problems. Using the P1–P1 triangular element , we solve a small Navier–Stokes type variational inequality problem on a coarse mesh and solve a large Stokes type variational inequality problem for simple iteration or a large Oseen type variational inequality proble...

The purpose of this paper is to present an indirect boundary integral method for the oscillatory Stokes flow provided by the translational oscillations of two rigid spheres in an incompressible Newtonian fluid of infinite expanse. 1. Introduction. The study of oscillatory Stokes flows has a key role in the understanding of the biomechanics of blood flow, the Brownian motion, the motion of swimm...

An algorithm based on the finite element modified method of characteristics (FEMMC) is presented to solve convection–diffusion, Burgers and unsteady incompressible Navier–Stokes equations for laminar flow. Solutions for these progressively more involved problems are presented so as to give numerical evidence for the robustness, good error characteristics and accuracy of our method. To solve the...