EFFECTS OF CHEMICAL REACTION, HEAT AND MASS TRANSFER ON NON-LINEAR MHD LAMINAR BOUNDARY-LAYER FLOW OVER A WEDGE WITH SUCTION OR INJECTION

We study the viscous nanofluid flow over a non-isothermal wedge with thermal radiation. The entropy due to irreversible processes in the system may degrade the performance of the thermodynamic system. Studying entropy generation in the flow over a porous wedge gives insights into how the system is affected by irreversible processes, and indicate which thermo–physical parameters contribute most to entropy generation in the system. The bivariate spectral quasi-linearization method is used to find the convergent solutions of the model equations. The impact of significant parameters such as the Hartmann number, thermophoresis and Brownian motion parameter on the fluid properties is evaluated and discussed. The Nusselt number, skin friction coefficients and Sherwood number are determined. An analysis of the rate of entropy generation in the flow for various parameters is presented, and among other results, we found that the Reynolds number and thermal radiation contribute significantly to entropy generation.

This paper concerns with the modelling of an unsteady natural convective and higher order chemically reactive magnetohydrodynamics (MHD) fluid flow with the effect of heat and radiation absorption. The flow is generated through a vertical oscillating porous plate. Boundary layer approximations is carried out to establish a flow model which represents the time dependent momentum, energy and diffusion balance equations. Before being solved numerically, the governing partial differential equations (PDEs) were transformed into a set of nonlinear ordinary differential equation (ODEs) by using non-similar technique. A very efficient numerical approach solves the obtained nonlinear coupled ODEs so called Explicit Finite Difference Method (EFDM). An algorithm is implemented in Compaq Visual Fortran 6.6a as a solving tool. In addition, the stability and convergence analysis (SCA) is examined and shown explicitly. The advantages of SCA is its optimizes the accuracy of system parameters such as Prandtl number (P_r) and Schmidt number (S_c).The velocity, temperature and concentration fields in the boundary layer region are studied in detail and the outcomes are shown in graphically with the influence of various pertinent parameters such as Grashof number (G_r), modified Grashof number (G_r), magnetic parameter (M), Darcy number (D_a),Prandtl number (P_r), Schmidt number (S_c), radiation (R), heat sink (Q),radiation absorption (Q₁), Eckert number (E_c), Dufour number (D_u),Soret number (S_r), Schmidt number (S_c), reaction index (P) and chemical reaction (K_r). Furthermore, the effect of skin friction coefficient (C_f), Nusselt number (N_u) and Sherwood number (S_h) are also examined graphically.

In the present article, the problem of boundary layer flow of MHD electrically conducting fluid past a cone and a wedge with non-uniform heat source/sink along with Cattaneo-Christov heat flux is investigated numerically. At first, the flow equations are converted into ODE via appropriate self similarity transforms and the resulting equations are solved with the assistance of R.-K. and Newton’s methods. The influence of several dimensionless parameters on velocity and temperature fields in addition to the friction factor and reduced heat transfer coefficient has been examined with the support of graphs and numerical values. The heat transfer phenomenon in the flow caused by the cone is excessive when compared to the wedge flow. Also, the thermal and momentum boundary layers are not the same for the flow over a cone and wedge.

In this article, we have considered the simultaneous influence of ohmic heating and chemical reaction on heat and mass transfer over a stretching sheet. The effects of applied magnetic field are also taken into consideration while the induced magnetic field is not considered due to very small magnetics Reynolds number. The governing flow problem comprises of momentum, continuity, thermal energy and concentration equation which are transformed into highly nonlinear coupled ordinary differential equations by means of similarity transforms, which are then, solved numerically with the help of Successive Linearization method (SLM) and Chebyshev Spectral collocation method. Numerical values of skin friction coefficient, local Nusselt number, and Sherwood number are also taken into account with the help of tables. The physical influence of the involved parameters of flow velocity, temperature and concentration distribution is discussed and demonstrated graphically. The numerical comparison is also presented with the existing published results and found that the present results are in excellent agreement which also confirms the validity of the present methodology.

This paper reports the magnetohydrodynamic chemically reacting Casson and Maxwell fluids past a stretching sheet with cross diffusion, non-uniform heat source/sink, thermophoresis and Brownian motion effects. Numerical results are obtained by employing the R-K based shooting method. Effects of pertinent parameters on flow, thermal and concentration fields are discussed with graphical illustrations. We presented the tabular results to discuss the nature of the skin friction coefficient, reduced Nusselt and Sherwood numbers. Dual nature is observed in the solution of Casson and Maxwell fluids. It is also observed a significant increase in heat and mass transfer rate of Maxwell fluid when compared with the Casson fluid.

The aim of this work is to study the effect non-uniform single and double slot suction (injection) on an unsteady mixed convection boundary layer flow over a vertical wedge with chemical reaction and heat generation or absorption. The unsteadiness is caused by the time dependent free stream velocity varying arbitrarily with time. Non-similar solutions are obtained by solving the coupled non-linear partial differential equations using the quasi-linearization technique in combination with an implicit finite-difference scheme and numerical computations are carried out for different values of dimensionless parameters to display the effects of non-uniform single and double slot suction (injection) along with chemical reaction and heat generation or absorption. Results indicate that the skin friction, heat and mass transfer coefficients increase with non-uniform slot suction but the effect of non-uniform slot injection is just the opposite. As the slot moves in downstream direction, the skin friction, heat and mass transfer coefficients decrease by non-uniform slot suction whereas non-uniform slot injection has the reverse effect.