Zahir Shah

Entropy Generation on Nanofluid Thin Film Flow of Eyring–Powell Fluid with Thermal Radiation and MHD Effect on an Unsteady Porous Stretching Sheet

This research paper investigates entropy generation analysis on two-dimensional nanofluid film flow of Eyring–Powell fluid with heat amd mass transmission over an unsteady porous stretching sheet in the existence of uniform magnetic field (MHD). The flow of liquid films are taken under the impact of thermal radiation. The basic time dependent equations of heat transfer, momentum and mass transfer are modeled and converted to a system of differential equations by employing appropriate similarity transformation with unsteady dimensionless parameters. Entropy analysis is the main focus in this work and the impact of physical parameters on the entropy profile are discussed in detail. The influence of thermophoresis and Brownian motion has been taken in the nanofluids model. An optima approach has been applied to acquire the solution of modeled problem. The convergence of the HAM (Homotopy Analysis Method) has been presented numerically. The disparity of the Nusslet number, Skin friction, Sherwood number and their influence on the velocity, heat and concentration fields has been scrutinized. Moreover, for comprehension, the physical presentation of the embedded parameters are explored analytically for entropy generation and discussed.

Three-dimensional rotating flow of MHD single wall carbon nanotubes over a stretching sheet in presence of thermal radiation

In this article the modeling and computations are exposed to introduce the new idea of MHD three-dimensional rotating flow of nanofluid through a stretching sheet. Single wall carbon nanotubes (SWCNTs) are utilized as a nano-sized materials while water is used as a base liquid. Single-wall carbon nanotubes (SWNTs) parade sole assets due to their rare structure. Such structure has significant optical and electronics features, wonderful strength and elasticity, and high thermal and chemical permanence. The heat exchange phenomena are deliberated subject to thermal radiation and moreover the impact of nanoparticles Brownian motion and thermophoresis are involved in the present investigation. For the nanofluid transport mechanism, we implemented the Xue model (Xue, Phys B Condens Matter 368:302–307, 2005). The governing nonlinear formulation based upon the law of conservation of mass, quantity of motion, thermal field and nanoparticles concentrations is first modeled and then solved by homotopy analysis method (HAM). Moreover, the graphical result has been exposed to investigate that in what manner the velocities, heat and nanomaterial concentration distributions effected through influential parameters. The mathematical facts of skin friction, Nusselt number and Sherwood number are presented through numerical data for SWCNTs.

Three-dimensional magnetohydrodynamic (MHD) flow of Maxwell nanofluid containing gyrotactic micro-organisms with heat source/sink

This paper discusses the three-dimensional flow of Maxwell nanofluid containing gyrotactic micro-organisms over a stretching surface. The effects of magnetic field and heat source/sink are also considered. Theory of microorganisms is utilized to stabilize the suspended nanoparticles through bioconvection induced by the effects of buoyancy forces. HAM (homotopy analysis method) is used to acquire analytic solution for the governing nonlinear equations. The effects of Deborah number, Hartmann number, mixed convection parameter, buoyancy ratio parameter, bioconvection Rayeigh number, stretching ratio parameter, brownian diffusion and thermophoresis diffusion parameters, Prandtl number, Lewis number, micro-organisms concentration difference parameter, bioconvection Peclet number and the bioconvection Lewis number on velocity, temperature, density of motile microorganisms and nanoparticle concentration are discussed graphically. The local Nusselt, Sherwood and motile micro-organisms numbers are also analyzed graphically. The reduction of the boundary layer thickness and velocity due to magnetic field is noted. The heat source/sink parameter have opposite effects on the temperature profile. We found that In comparison to the case of heat sink the thermal boundary layer thickness and temperature increases in the case of heat source.This paper discusses the three-dimensional flow of Maxwell nanofluid containing gyrotactic micro-organisms over a stretching surface. The effects of magnetic field and heat source/sink are also considered. Theory of microorganisms is utilized to stabilize the suspended nanoparticles through bioconvection induced by the effects of buoyancy forces. HAM (homotopy analysis method) is used to acquire analytic solution for the governing nonlinear equations. The effects of Deborah number, Hartmann number, mixed convection parameter, buoyancy ratio parameter, bioconvection Rayeigh number, stretching ratio parameter, brownian diffusion and thermophoresis diffusion parameters, Prandtl number, Lewis number, micro-organisms concentration difference parameter, bioconvection Peclet number and the bioconvection Lewis number on velocity, temperature, density of motile microorganisms and nanoparticle concentration are discussed graphically. The local Nusselt, Sherwood and motile micro-organisms numbers are also analyzed g...

Radiative MHD thin film flow of Williamson fluid over an unsteady permeable stretching sheet

In this research work we have examined the flow of Williamson liquid film fluid with heat transmission and having the impact of thermal radiation embedded in a permeable medium over a time dependent stretching surface. The fluid flow of liquid films is assumed in two dimensions. By using suitable similarity transformation the governing non-linear partial differential equations have been transformed into non-linear differential equations. An optimal approach has been used to acquire the solution of the modelled problem. The convergence of the technique has been shown numerically. The impact of the Skin friction and Nusslet number and their influence on thin film flow are shown numerically. Thermal radiation, unsteadiness effect and porosity have mainly focused in this paper. Furthermore, for conception and physical demonstration the entrenched parameters, like porosity parameter k, Prandtl number Pr, unsteadiness parameter S, Radiation parameter Rd, Magnetic parameter M, and Williamson fluid parameter have been discussed graphically in detail with their effect on liquid film flow.

Study of two-dimensional boundary layer thin film fluid flow with variable thermo-physical properties in three dimensions space

The conversion of study in two dimensional (x, y) medium into three dimensions space (x, y, z) of a magnetohydrodynamic mixed convective heat and mass transfer boundary layer flow of a thin film second-grade fluid with temperature dependent viscosity and thermal conductivity in the presence of thermal radiation and viscous dissipation past a stretching sheet is analyzed. The occurrence of Hall current in two dimensional (x, y) medium produces a force in z-direction which generates a cross flow in that direction and so the motion is made in three dimensions space (x, y, z). Similarity transformations are used and the transformed system of equations of the problem has been solved by utilizing homotopy analysis method. The salient impacts of the emerging parameters on velocities, temperature and concentration fields have been displayed graphically and illustrated.The conversion of study in two dimensional (x, y) medium into three dimensions space (x, y, z) of a magnetohydrodynamic mixed convective heat and mass transfer boundary layer flow of a thin film second-grade fluid with temperature dependent viscosity and thermal conductivity in the presence of thermal radiation and viscous dissipation past a stretching sheet is analyzed. The occurrence of Hall current in two dimensional (x, y) medium produces a force in z-direction which generates a cross flow in that direction and so the motion is made in three dimensions space (x, y, z). Similarity transformations are used and the transformed system of equations of the problem has been solved by utilizing homotopy analysis method. The salient impacts of the emerging parameters on velocities, temperature and concentration fields have been displayed graphically and illustrated.

Simulation of bioconvection in the suspension of second grade nanofluid containing nanoparticles and gyrotactic microorganisms

A time dependent symmetric flow with heat transmission of a second-grade fluid containing nanoparticles and gyrotactic microorganisms between two parallel plates in two dimensions is explored. Partial differential equations furnish the nonlinear ordinary differential equations due to the usage of relevant similarity transformations. Motion declines due to second grade fluid, energy elevates due to thermophoresis, concentration enhances due to Brownian motion and gyrotactic microorganisms profile elevates due to Peclet number. The unsteadiness parameter β has profound effect on the nanobioconvection flow within the plates. Optimal homotopy asymptotic method (OHAM) is followed to evaluate the transformed systems. Consistency and smoothness between the first and second orders of the optimal homotopy asymptotic method are revealed through graphs. Also, graphs are provided to manifest the impacts of each parameter.A time dependent symmetric flow with heat transmission of a second-grade fluid containing nanoparticles and gyrotactic microorganisms between two parallel plates in two dimensions is explored. Partial differential equations furnish the nonlinear ordinary differential equations due to the usage of relevant similarity transformations. Motion declines due to second grade fluid, energy elevates due to thermophoresis, concentration enhances due to Brownian motion and gyrotactic microorganisms profile elevates due to Peclet number. The unsteadiness parameter β has profound effect on the nanobioconvection flow within the plates. Optimal homotopy asymptotic method (OHAM) is followed to evaluate the transformed systems. Consistency and smoothness between the first and second orders of the optimal homotopy asymptotic method are revealed through graphs. Also, graphs are provided to manifest the impacts of each parameter.