Mohammad Mainul Hoque

Numerical simulation of Dean number and curvature effects on magneto-biofluid flow through a curved conduit.

A numerical study is performed to investigate the magnetohydrodynamic viscous steady biofluid flow through a curved pipe with circular cross section under various conditions. A spectral method is applied as the principal tool for the numerical simulation with Fourier series, Chebyshev polynomials, collocation methods and an iteration method as secondary tools. The combined effects of Dean number, Dn, magnetic parameter, Mg, and tube curvature, δ, are studied. The flow patterns have been shown graphically for large Dean numbers as well as magnetic parameter and a wide range of curvatures, 0.01 ≤δ≤ 0.2. Two-vortex solutions have been found. Axial velocity has been found to increase with an increase of Dean number, whereas it is suppressed with greater curvature and magnetic parameters. For high magnetic parameter and Dean number and low curvature, almost all the fluid vortex strengths are weak. The study is relevant to magnetohydrodynamic blood flow in the cardiovascular system.

Multiple slip effects on magnetic-Carreau fluid in a suspension of gyrotactic microorganisms over a slendering sheet

A computational simulation of two-dimensional magnetic-Carreau fluid in a suspension of gyrotactic microorganisms past a slendering sheet with variable thickness is investigated for slenderness parameters varied in the range of –0.2 to 1.0. Owing to the noticeable implication in various engineering applications, the effects of multiple slip is considered in the present simulation along with the Soret and the Dufour effects for the heat and mass transfer controlling process. The numerical values of the velocity, temperature, concentration, and the density of the motile organisms are computed by the robust Runge–Kutta-based Newton’s scheme. The thermal and concentration boundary layer are changed with the increase in the multiple slip parameters such as velocity slip, temperature slip, concentration slip, and diffusion slip parameters. With the rise in the Carreau fluid power index parameter, the velocity field increases while it declines with the velocity slip and magnetic field parameter. The increasing values of velocity slip, Dufour number, Soret number, and magnetic parameter boost up the density of the motile organism profiles for different slenderness parameter considered in the present study. The effect of the nondimensional factors on the skin friction, local Nusselt, local Sherwood, and the density numbers of the motile organisms are discussed with the assistance of the table for three different slenderness parameters. It is found that multiple slip parameters enable to control the heat and mass transfer rate. Finally, both the qualitative and quantitative comparisons of the present results with previous study are presented in the tabular form and are found to be in excellent agreement.

Heat transfer effect on MHD flow of a micropolar fluid through porous medium with uniform heat source and radiation

Abstract The present study examines the effect of heat transfer on electrically conducting MHD micropolar fluid flow along a semi-infinite horizontal plate with radiation and heat source. The uniform magnetic field has applied along the principal flow direction. The obtained governing equations have been converted into a set of dimensionless differential equations and then numerically solved by using a well-known Runge-Kutta method with shooting technique. The velocity, microrotation, and temperature distribution are presented for various physical parameters. The numerical values of skin friction and Nusselt numbers at the plates are shown in tabular form, and the obtained results are compared with the results of a previous study. It has been found that the magnetic parameter increases the velocity profile whereas the boundary layer thickness reduces due to the inclusion of coupling parameter and inertia effect. The presence/absence of magnetic parameter and coupling parameter enable to enhance the angular velocity profile while it is worth to note that the backflow has generated in the vicinity of the plate.