Mohammad Wahiduzzaman

MHD boundary layer radiative, heat generating and chemical reacting flow past a wedge moving in a nanofluid

The present study analyzed numerically magneto-hydrodynamics (MHD) laminar boundary layer flow past a wedge with the influence of thermal radiation, heat generation and chemical reaction. This model used for the momentum, temperature and concentration fields. The principal governing equations is based on the velocity uw(x) in a nanofluid and with a parallel free stream velocity ue(x) and surface temperature and concentration. Similarity transformations are used to transform the governing nonlinear boundary layer equations for momentum, thermal energy and concentration to a system of nonlinear ordinary coupled differential equations with fitting boundary conditions. The transmuted model is shown to be controlled by a number of thermo-physical parameters, viz. the magnetic parameter, thermal convective parameter, mass convective parameter, radiation-conduction parameter, heat generation parameter, Prandtl number, Lewis number, Brownian motion parameter, thermophoresis parameter, chemical reaction parameter and pressure gradient parameter. Numerical elucidations are obtained with the legendary Nactsheim-Swigert shooting technique together with Runge–Kutta six order iteration schemes. Comparisons with previously published work are accomplished and proven an excellent agreement.

SPECTRAL NUMERICAL SIMULATION OF MAGNETO-PHYSIOLOGICAL LAMINAR DEAN FLOW

A computational simulation of magnetohydrodynamic laminar blood flow under pressure gradient through a curved bio-vessel, with circular cross-section is presented. Electrical conductivity and other properties of the biofluid (blood) are assumed to be invariant. A Newtonian viscous flow (Navier–Stokes magnetohydrodynamic) model is employed which is appropriate for large diameter blood vessels, as confirmed in a number of experimental studies. Rheological effects are therefore neglected as these are generally only significant in smaller diameter vessels. Employing a toroidal coordinate system, the steady-state, three-dimensional mass and momentum conservation equations are developed. With appropriate transformations, the transport model is non-dimensionalized and further simplified to a pair of axial and secondary flow momenta equations with the aid of a stream function. The resulting non-linear boundary value problem is solved with an efficient, spectral collocation algorithm, subject to physically appropriate boundary conditions. The influence of magnetic body force parameter, Dean number and vessel curvature on the flow characteristics is examined in detail. For high magnetic parameter and Dean number and low curvature, the axial flow is observed to be displaced toward the center of the vessel with corresponding low fluid particle vorticity strengths. Visualization is achieved with the MAPLE software. The simulations are relevant to cardiovascular biomagnetic flow control.

MHD Free Convection and Mass Transfer Flow from a Vertical Plate in the Presence of Hall and Ion-Slip Current:

MHD free convection and mass transfer flow over a continuously moving vertical porous plate under the action of strong magnetic field is investigated. In this analysis the hall and ion-slip current in the momentum equation are considered for high speed fluid flows and the level of concentration of foreign mass have been taken very high. The governing equations of the problem contain a system of partial differential equations. The coupled partial differential equations are solved numerically by explicit finite difference method. The results of this investigation are discussed for the different values of the well-known parameters with different time steps. Finally, the obtained finite difference solutions are compared with analytical solution by the graphical representation.

MHD flow of fluid over a rotating inclined permeable plate with variable reactive index

MHD free convection, heat and mass transfer flow over a rotating inclined permeable plate with the influence of magn etic field, thermal radiation and chemical reaction of various order has been investigated numerically. The governing boundary - layer equations are formulated and transformed into a set of similarity equations with the help of similarity variables derived b y lie group transformation. The governing equations are solved numerically using the Nactsheim - Swigert Shooting iteration technique together with the Runge - Kutta six order iteration schemes. The simulation results are presented graphically to illustrate in fluence of magnetic parameter

Magnetic field effect on fluid flow through a rotating rectangular straight duct with large aspect ratio

Numerical study has been performed to investigate the fluid flow through a rotating rectangular straight duct in the presence of magnetic field under various flow conditions. Spectral method is applied as a main tool for the numerical calculation technique, where the Chebyshev polynomial, collocation method and the Newton-Raphson method are also used as secondary tools. The magnetohydrodynamic incompressible viscous steady fluid flow through a straight duct of rectangular cross-section rotating at a constant angular velocity about the centre of the duct cross-section is investigated to examine the combined effects of magnetic parameter ( M g ), rotational parameter ( T r ), pressure driven parameter ( D n ) and aspect ratio (γ). One of the interesting phenomena of the flow is the solution curve and the flow structure. The flow structures in case of rotation of the duct axis, the pressure driven parameters with large magnetic parameters well as large rotational parameters are examined while other parameters remain constant. The calculations are carried out for 5 ≤ M g ≤ 50,000, 50 ≤ T r ≤ 100,000, D n = 500, 1,000, 1,500 and 2,000 where the aspect ratio 3.0.

Non-isothermal flow through a rotating straight duct with wide range of rotational and pressure driven parameters

AbstractNumerical study is performed to investigate the Non-isothermal flow in a rotating straight duct under various flow conditions. Spectral method is applied as a main tool for the numerical technique, where the Chebyshev polynomial, the Collocation methods, the Arc-length method and the Newton-Raphson method are also used as secondary tools. The characteristics of the flow mentioned above are described here. The incompressible viscous steady Non-isothermal flow through a straight duct of rectangular cross-section rotating at a constant angular velocity about the center of the duct cross-section is investigated numerically to examine the combined effects of Rotation parameter (Coriolis force), Grashof number (parameter which is used in heat, transfer studies involving free, forced or natural convection and is equql to

Viscous Dissipation and Radiation Effects on MHD Boundary Layer Flow of a Nanofluid Past a Rotating Stretching Sheet

\frac{{L^3 g\beta \Delta {\rm T}}} {{v^2 }}

Numerical investigation of radiative optically-dense transient magnetized reactive transport phenomena with cross diffusion, dissipation and wall mass flux effects

, where L is the characteristic length, ρ the density, g the acceleration due to gravity, β the thermal expansion coefficient, ΔT the temperature difference, μ the viscosity and ν the kinematic viscosity of the fluid. The expansion coefficient β is a measure of the rate at which the volume V of the fluid changes with temperature at a given pressure P), Prandtl number, aspect ratio and Pressure-driven parameter (centrifugal force) on the flow. We examine the structures in case of rotation of the duct axis and the Pressure-driven parameter with large aspect ratio where other parameters are fixed. The calculations are carried out for 0 ≤ Tr ≤ 300, 2 ≤ γ ≤ 6, Gr = 100, Pr = 7.0 and 0 ≤ Pr ≤ 800 by applying the Spectral method. When Ω > 0 and the rotation is in the same direction as the Coriolis force enforces the centrifugal force, multiple solutions of Non-symmetric the secondary flow patterns with 10-vortex (maximum) are obtained in case of Tr = 100 and 150 with large aspect ratio. The intense of the temperature field is very strong near the heated wall in all cases. Finally, the overall solutions of the problems considered in conclusion.