Dual Solutions for MHD Stagnation-point Flow of a Nanofluid Over a Stretching Surface with Induced Magneticfield

Present study deals with the buoyancy-driven MHD mixed convection stagnation-point flow, heat and mass transfer of a nanofluid over a non-isothermal stretching sheet in presence of induced magneticfield, radiation, chemical reaction, suction/injection and heat source/sink. The basic governing partial differential equations are reduced to a set of ordinary differential equations by using appropriate similarity transformation. The resulting system is solved numerically by bvp5c Matlab package. Numerical results are validated by comparing with the published results. The influence of non-dimensional governing parameters on velocity, induced magneticfield, temperature and concentration profiles along with coefficient of skin friction, local Nusselt and Sherwood numbers are discussed and presented with the help of graphs and tables. Comparisons are made with the existed studies. Results indicate that dual solutions exists only for certain range of suction/ injection parameter and injection parameter have tendency to enhance the momentum, thermal and concentration boundary layer thickness

MHD flow of dusty nanofluid over a stretching surface with volume fraction of dust particles

AbstractIn this study we analyzed the momentum and heat transfer behavior of MHD nanofluid embedded with conducting dust particles past a stretching surface in the presence of volume fraction of dust particles. The governing equations of the flow and heat transfer are transformed into nonlinear ordinary differential equations by using similarity transformation and then solved numerically using Runge–Kutta based shooting technique. The effect of non-dimensional governing parameters on velocity and temperature profiles of the flow are discussed and presented through graphs. Additionally friction factor and the Nusselt number have also been computed. Under some special conditions, numerical results obtained by the present study were compared with the existed studies. The result of the present study proves to be highly satisfactory. The results indicate that an increase in the interaction between the fluid and particle phase enhances the heat transfer rate and reduces the friction factor

Heat and mass transfer in radiative MHD Carreau fluid with cross diffusion

Numerical investigation is carried out for analyzing the heat and mass transfer in Carreau fluid flow over a permeable stretching sheet with convective slip conditions in the presence of applied magnetic field, nonlinear thermal radiation, cross diffusion and suction/injection effects. The transformed nonlinear ordinary differential equations with the help of similarity variables are solved numerically using Runge-Kutta and Newton’s methods. We presented dual solutions for suction and injection cases. The effect of non-dimensional governing parameters on velocity, temperature and concentration profiles are discussed and presented through graphs. Numerical values of friction factor, local Nusselt and Sherwood numbers are tabulated. We found an excellent agreement of the present results by comparing with the published results. It is found that Soret and Dufour parameters regulate the heat and mass transfer rate. Nonlinear thermal radiation effectively enhances the thermal boundary layer thickness. Keywords: MHD, Carreau fluid, Stretching/shrinking sheet, Cross diffusion, Thermal radiatio

MHD flow over a permeable stretching/shrinking sheet of a nanofluid with suction/injection

In this study we analyzed the influence of thermal radiation and chemical reaction on two dimensional steady magnetohydrodynamic flow of a nanofluid past a permeable stretching/shrinking sheet in the presence of suction/injection. We considered nanofluid volume fraction on the boundary is submissive controlled, which makes the present study entirely different from earlier studies and physically more realistic. The equations governing the flow are solved numerically. Effects of non-dimensional governing parameters on velocity, temperature and concentration profiles are discussed and presented through graphs. Also, coefficient of skin friction and local Nusselt number is investigated for stretching/shrinking and suction/injection cases separately and presented through tables. Comparisons with existed results are presented. Present results have an excellent agreement with the existed studies under some special assumptions. Results indicate that the enhancement in Brownian motion and thermophoresis parameters depreciates the nanoparticle concentration and increases the mass transfer rate. Dual solutions exist only for certain range of stretching/shrinking and suction/injection parameters

Boundary layer analysis of persistent moving horizontal needle in Blasius and Sakiadis magnetohydrodynamic radiative nanofluid flows

The boundary layer of a two-dimensional forced convective flow along a persistent moving horizontal needle in an electrically conducting magnetohydrodynamic dissipative nanofluid was numerically investigated. The energy equation was constructed with Joule heating, viscous dissipation, uneven heat source/sink, and thermal radiation effects. We analyzed the boundary layer behavior of a continuously moving needle in Blasius (moving fluid) and Sakiadis (quiescent fluid) flows. We considered Cu nanoparticles embedded in methanol. The reduced system of governing Partial differential equations (PDEs) was solved by employing the Runge–Kutta-based shooting process. Computational outcomes of the rate of heat transfer and friction factors were tabulated and discussed. Velocity and temperature descriptions were examined with the assistance of graphical illustrations. Increasing the needle size did not have a significant influence on the Blasius flow. The heat transfer rate in the Sakiadis flow was high compared with that in the Blasius flow

Heat and mass transfer in 3-D MHD Williamson-Casson fluids flow over a stretching surface with non-uniform heat source/sink

A mathematical model has been proposed for investigating the flow, heat, and mass transfer in Williamson and Casson fluid-flow over a stretching surface. For controlling the temperature and concentration fields we considered the space and temperature dependent heat source/sink and homogeneous-heterogeneous reactions, respectively. Numerical results are carried out for this study by using Runge-Kutta based shooting technique. The effects of governing parameters on the flow, heat and mass transfer are illustrated graphically. Also computed the skin-friction coefficients for axial and transverse directions along with the local Nusselt number. In most of the studies, homogeneous-heterogeneous profiles were reduced into a single concentration equation by assuming equal diffusion coefficients. For the physical relevance, without any assumptions we studied the individual behavior of the homogeneous-heterogeneous profiles. It is found that the rate of heat and mass transfer in Casson fluid is significantly large while equated with the heat and mass transfer rate of Williamson fluid