Ahmad Zeeshan

Study of Natural Convection MHD Nanofluid by Means of Single and Multi-Walled Carbon Nanotubes Suspended in a Salt-Water Solution

The natural convection boundary layer flow along a vertical cone with variable wall temperature under the presence of magnetohydrodynamics is investigated. The mathematical model based on nanolayer single and multi-wall carbon nanotubes in salt-water solutions and interfacial layers is considered. The nonlinear partial differential equations are analytically solved by means of Mathematica package BVPh 2.0 based on the homotopy analysis method. Flow behavior under altering involving physical parameters such as: Eckert number, Prandtl number, power law index, and nanoparticle volume fraction on the velocity and the temperature profiles is discussed and explained through graphs and tables. The values of Skin friction and Nusselt number are computed and examined.

The shape effects of nanoparticles suspended in HFE-7100 over wedge with entropy generation and mixed convection

The flow of mixed convection nanofluid over wedge under the effects of porous medium is investigated. The HFE-7100 Engineered Fluid having Nimonic 80a metal nanoparticles of spherical and non-spherical shapes with different sizes is used. The particle shape effects on Bejan number and entropy generation are taken into account. The system of partial differential equations is first written in terms of ordinary differential equations using adequate similarity transformations and then solved analytically. Analytical solutions of the resulting equations are obtained for the velocity and temperature profiles. Simultaneous effects of porous medium, particle volume friction, mixed convection parameter, and angle of wedge in the presence of different shapes nanoparticles are demonstrated graphically. Effects of particle concentrations, sizes on wall stress, heat transfer coefficient of Skin friction, and Nusselt are discussed in the form of tables.

Heat transfer analysis in ferromagnetic viscoelastic fluid flow over a stretching sheet with suction

In this article, an investigation has been performed to explore the two-dimensional boundary layer flow problem and heat transfer characteristic of ferromagnetic viscoelastic fluid flow over a stretching surface with a linear velocity under the impact of magnetic dipole and suction. The governing PDEs are converted into a system of nonlinear ODEs by applying appropriate similarity approach. The modelled equations are then solved numerically by utilizing efficient Runge–Kutta–Fehlberg procedure based on shooting algorithm. Influence of pertinent flow parameter involved, such as ferromagnetic interaction parameter, suction parameter, viscoelastic parameter, Prandtl number on dimensionless velocity, temperature, skin friction, and Nusselt inside the boundary layer, are portrayed graphically and discussed. The results show that pressure profile and skin friction coefficient increase with the variation of ferromagnetic interaction parameter and opposite behaviour is noted for local Nusselt number.

Hydromagnetic nanofluid flow past a stretching cylinder embedded in non-Darcian Forchheimer porous media

AbstractThe present article presents the hydromagnetic nanofluid flow past a stretching cylinder embedded in non-Darcian Forchheimer porous media by using Buongiorno’s mathematical model (Buongiorno in J Heat Transf 128:240–250, 2006; Nadeem et al. in J Taiwan Inst Chem Eng 45:121, 2014, Nadeem et al. Appl Nanosci 4:625–631, 2014). Thermal radiation via Roseland’s approximation (Akbar et al. in Chin J Aeronaut 26:1389–1397, 2013; Nadeem and Haq in J Aerosp Eng 28:04014061, 2012), Brownian motion, thermophoresis and Joule heating effects are also considered. To explore thermal characteristics, prescribed heat flux and prescribed mass flux boundary conditions are deployed. Governing flow problem consists of PDEs in the cylindrical form, which are converted into system of nonlinear ODEs by applying applicable similarity transforms. ODEs are tackled by RK–Fehlberg fourth–fifth-order numerical integration scheme with shooting algorithm. Impact of numerous involving physical parameters on flow features like temperature distribution, velocity distribution, Sherwood number, local Nusselt number and skin friction coefficient is shown through graphs and tables.

Electromagnetohydrodynamic transport of Al2O3 nanoparticles in ethylene glycol over a convectively heated stretching cylinder

In this study, the transport of Al2O3 nanoparticles in ethylene glycol conventional fluid over a linearly stretching cylinder is investigated. The current research employs a convective surface boundary condition for heat transfer exploration. Flux model proposed by Rosseland is employed to examine effect of thermal radiations. The governing flow problem comprises highly nonlinear ordinary differential equations. Similarity transformations are used to reduce the equations in similar forms, which are then solved by Runge–Kutta–Fehlberg fourth-fifth order numerical scheme with shooting algorithm in MATLAB software. In order to authenticate the accuracy of our results, we have contrasted results with those obtained by Ishak et al., Wang, and Pandey and Kumar and found that they are in better concord, as revealed in Table 2. The impact of numerous emerging parameters on velocity distribution and heat transfer distribution are argued in all aspects and depicted through graphs.

Hydromagnetic solid–liquid pulsatile flow through concentric cylinders in a porous medium

The current research is reported about the hydromagnetic solid–liquid flow in an annulus between two concentric circular cylinders embedded in a porous media. The impact of joule heating is also accounted for. Unlike the usually applied constant pressure gradient, the pulsatile pressure gradient is employed. The flow problem is first modeled and then tackled by Runge–Kutta–Fehlberg fourth–fifth-order (RKF45) numerical scheme along with shooting algorithm. The impacts of emerging parameters namely magnetic field parameter and porosity parameter on velocity and temperature distributions are displayed through graphs and briefly addressed.Graphical abstract

MIXED CONVECTION FLOW AND HEAT TRANSFER IN FERROMAGNETIC FLUID OVER A STRETCHING SHEET WITH PARTIAL SLIP EFFECTS

Two-dimensional steady boundary layer mixed convection flow and heat transfer in ferromagnetic fluid over a stretching sheet is investigated. Velocity slip is taken into account. The governing partial differential equations are first transformed into the non-linear ordinary coupled differential equation using a similarity transformation and then solved numerically by Runge-Kutta-Fehlberg method. The role of local skin friction, heat transfer rate, ferromagnetic-interaction parameter, slip parameter and the buoyancy parameter on velocity and temperature profiles inside the boundary layers are examined through tables and graphically. Finally a comparison is also made with the existing literature and found in good agreement.