MHD stagnation point flow of Williamson and Casson fluids past an extended cylinder: a new heat flux model

Abstract

The impact of heat transfer in MHD flows along a stretching cylinder is playing a vital role for heat exchangers, fiber coating, transportation, etc. Currently, a lot of theoretical models are accessible for illustrating the thermal transfer impact of non-Newtonian liquid flows over a cylinder. Also, an external magnetic force is spot-on to deal with the physical features of the fluids to oversee the nature of thermal and momentum transfer in the system. Considering this fact, we inspect the heat transport behavior of two different non-Newtonian MHD flows due to stretching of a cylinder with heat generation, by taking the advantage of a new heat flux theory conceived by Christov-Cattaneo. The basic PDEs are converted into ODEs with the suitable similarity transformations. These ODEs are solved by fourth order Runge-Kutta based shooting system. Plots are drawn to discern the influence of sundry parameters on the flow fields (velocity and temperature). Along with them the rate of heat transfer and friction factor are bestowed in table. From the results, we notice that the influence of thermal stratification and curvature parameters have a propensity to increase both the velocity and thermal fields. Thermal relaxation parameter effectively lifts the friction factor in the flow of Williamson fluid than that of Casson fluid. Keywords MHD • Heat transfer • Non-Newtonian fluid • Convection • Thermal stratification • Cylinder List of symbols B 0 Applied magnetic field strength b Radius of the cylinder C f Friction factor Gr Grashof number J m Wall shear stress J w The measure of the heat transfer k Thermal conductivity l 0 Characteristic length M Magnetic field parameter m 1 , m 2 Constants Nu Nusselt number Pr Prandtl number p 0 & p ∞ Velocity components c p Specific heat Q l Component of heat source Q Heat source parameter S Thermal stratification parameter T Temperature of the fluid T 0 Component of temperature V r Velocity ratio parameter u, v Velocity components in x, y− directions u e Free stream velocity u w Stretching velocity of the cylinder Greek letters Thermal relaxation parameter Viscosity (kinematic) Electrical conductivity T Thermal expansion coefficient Relaxation time of heat flux Fluid's density Positive time constant Casson fluid parameter Williamson fluid parameter Stream function

Radiative Magnetohydrodynamics Casson Nanofluid Flow and Heat and Mass Transfer past on Nonlinear Stretching Surface

“…The 2D mixed convection MHD boundary layer stagnation point flow in the existence of thermal radiation using a vertical plate which was filled with nanofluid has been demonstrated by Eftekhari and Moradi [10]. Kumar et al [11] analyzed the impact of the transfer of heat in MHD Casson nanofluid using nonlinear surface. Aman et al [12] investigated the flow of 2D incompressible viscous fluid using a shrinking surface in the existence of an external magnetic field.…”

3-D magnetohydrodynamic AA7072-AA7075/methanol hybrid nanofluid flow above an uneven thickness surface with slip effect

“…The system of ODE's (10)(11)(12) along the boundary restrictions (13) are resolved numerically using R-K based shooting procedure 14 www.nature.com/scientificreports www.nature.com/scientificreports/ to attain the required results. Above quantities are reserved for the complete study, unless they specified in respective graphs and tables.…”

Unsteady magnetohydrodynamic radiative liquid thin film flow of hybrid nanofluid with thermophoresis and Brownian motion

“…On a similar note the analytical study conducted by Sulochana and Aparna (2019) has revealed that pertinent magnetic field have the tendency to depreciate fluid velocity profile. Furthermore, Kumar et al (2019) illustrated the heat transfer impact on MHD Williamson and Casson fluids flow at a stagnation point and validated results. Acharya et al (2018a, b) in their study demonstrated the carbon nanotube flow past a stretching sheet under the influence of magnetic field and illustrated graphically the amplification of fluid's thermal designation due to magnetic parameter.…”

“…A similarity solution for unsteady magnetized nanoliquid flow with thermophoretic and Brownian motion effects was obtained by Ramana Reddy et al (2018). Numerical solution of nanoliquids with impact of Brownian motion and thermophoresis was effectuated by authors (Anantha Kumar et al, 2019;Ullah et al, 2019).…”