Browsing by Author "Swati Mukhopadhyay"

Now showing 1 - 2 of 2

Impacts of activation energy and binary chemical reaction on MHD flow of Williamson nanofluid in Darcy–Forchheimer porous medium: a case of expanding sheet of variable thickness
(Taylor and Francis Ltd., 2024) Anil Kumar Gautam; Ajeet Kumar Verma; Krishnendu Bhattacharyya; Swati Mukhopadhyay; Ali J. Chamkha
An expanding sheet problem is more relevant when the thickness of the sheet is variable and it bears frequent applications in polymer press, paper production, metallic plate cooling, etc. On the other hand, activation energy is an important phenomenon of chemical reaction in flow dynamics of Newtonian and non-Newtonian fluids. The activation energy and chemical reaction have vital applications in food preparing, the mechanism of water and oil emulsions, chemical engineering, and more. So in this project, the impacts of activation energy and binary chemical reaction on MHD two-dimensional boundary layer flow of Williamson nanofluid on an expanding surface of variable thickness embedded in Darcy–Forchheimer porous medium are investigated. Using suitable transformations, the governing equations are transformed into a set of non-linear ordinary differential equations (ODEs). Later, numerical solutions have been achieved by well-known MATLAB inbuilt function ‘bvp4c’. Several vital results are explored for variations of involved physical parameters and those are presented in graphical and tabular modes. The achieved results suggest that when wall thickness parameter increases, there is a contrast in behaviors of velocity, temperature and nanoparticle concentration if there is a condition that the shape parameter is greater than or less than unity. For the former case, the above flow properties reduce with wall thickness parameter, whereas, for the latter case, those are showing significant growth. The Brownian motion of nanoparticles causes an increase in temperature and a reduction in nanoparticle concentration, whereas due to thermophoretic force, both temperature and nanoparticle concentration rise. Due to the presence of activation energy in chemical reaction, the nanoparticle concentration enhances, while, temperature decreases(increases) near(away from) the sheet. With increasing reaction rate parameters, nanoparticle concentration diminishes, but temperature increases near the sheet. The surface drag force decreases with Williamson fluid parameter, while it increases with the magnetic parameter, inverse Darcy number, and Forchheimer parameter. On the other hand, the surface heat flux and surface mass flux are decreasing functions of Williamson fluid parameter, magnetic parameter, inverse Darcy number, and Forchheimer parameter. It also reveals that surface heat flux reduces with increasing reaction rate parameters, whereas surface mass flux increases. Finally, for the growth of activation energy parameter, initially surface heat flux rises and surface mass flux declines, but for its larger values, the quantities turn out to be constants. Also, the surface heat and mass fluxes are decreasing functions of thermophoresis parameter. © 2021 Informa UK Limited, trading as Taylor & Francis Group.
Insight into the convective heat transport in magnetohydrodynamic Casson liquid inside a wavy channel
(Canadian Science Publishing, 2025) Rampal Prasad; Mani Shankar Mandal; Swati Mukhopadhyay; Krishnendu Bhattacharyya
This research investigates the magnetohydrodynamic (MHD) behavior of a non-Newtonian Casson fluid flowing through a wavy channel with a localized heat source at the bottom wall, focusing on the interaction between magnetic field effects and thermal transport. The study uses the vorticity-stream function method to derive the vorticity transport equation along with the stream function equation. The resulting coupled, nonlinear MHD and energy equations, along with the relevant boundary conditions, are solved numerically using the finite difference method. Key flow parameters, including Reynolds number (Re), Rayleigh number (Ra), Casson parameter (β), Hartmann number (Ha), and Prandtl number (Pr), significantly affect fluid motion and temperature distribution. Findings show that increasing the Casson parameter (β) enhances fluid velocity and reduces the thickness of the thermal boundary layer near the heater. The Lorentz force suppresses convection, decreasing the heat transfer rate as the Hartmann number (Ha) rises. Additionally, the backflow region decreases with higher values of Prandtl number (Pr) and Reynolds number (Re). Moreover, the average Nusselt number (Nu) increases with Re and Pr, indicating better heat transfer under these conditions. © 2025, Canadian Science Publishing. All rights reserved.