MHD EFFECTS ON UNSTEDY DYNAMIC, THERMAL AND DIFFUSION BOUNDARY LAYER FLOW OVER A HORIZONTAL CIRCULAR CYLINDER

Abstract

This paper is devoted to the analysis of unsteady two-dimensional dynamic, hermal and diffusion magnetohydrodynamic laminar boundary layer flow over a orizontal circular cylinder of incompressible and electrical conductivity fluid, in porous medium, in the presence of a heat source or sink, and chemical eactions. The present magnetic field is homogenous and perpendicular to the ody surface. It is assumed that the induction of the outer magnetic field is the unction of the longitudinal coordinate and time. Fluid electrical conductivity is onstant. The outer electric field is neglected and the magnetic Reynolds number s significantly lower than one i. e. the considered the problem is in induction-less pproximation. Free stream velocity, temperature and concentration on the body re arbitrary differentiable functions. The developed governing boundary layer quations and associated boundary conditions are converted into a nondimensional orm using a suitable similarity transformation and similarity arameters. The system of dimensionless equations is solved using the finite ifference method and iteration method. Numerical results are obtained and resented for incompressible fluid for different numbers, such as Sc, Pr, Ec and agnetic number, and the parameter of the porous medium, temperature arameters, thermal parameter, diffusion parameters and chemical reaction arameter. The solutions for the flow, temperature and diffusion transfer and ther integral characteristics, boundary layer, are evaluated numerically for ifferent values of the magnetic field. Transient effects of velocity, temperature nd diffusion are analyzed. A part of obtained results is given in the form of igures and corresponding conclusions.

Keywords

Dates

  • Submission Date2012-05-03
  • Revision Date2012-06-25
  • Acceptance Date2012-07-05

DOI Reference

10.2298/TSCI120503171B

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