Eur. Phys. J. Plus (2020) 135: 249
https://doi.org/10.1140/epjp/s13360-019-00030-1

Regular Article

Entropy generation analysis in MHD flow of viscous fluid by a curved stretching surface with cubic autocatalysis chemical reaction

¹ Department of Mathematics, Quaid-I-Azam University 45320, Islamabad, 44000, Pakistan
² Nonlinear Analysis and Applied Mathematics (NAAM) Research Group, Faculty of Science, King Abdulaziz University, P. O. Box 80207, Jeddah, 21589, Saudi Arabia

^* e-mail: mikhan@math.qau.edu.pk

Received: 9 August 2019
Accepted: 17 September 2019
Published online: 14 February 2020

Abstract

Here characteristic of magnetohydrodynamic flow of viscous liquids due to curved stretchable surface is discussed. Behavior of energy equation is explored in the presence of heat generation, viscous dissipation and Joule heating. Physical behavior of entropy optimization rate is the key focus of this investigation. Cubic autocatalysis chemical reactions (homogeneous and heterogeneous reactions) are also accounted. The basic flow equations are obtained due to the implementation of curvilinear coordinates. Nonlinear partial differential expressions are reduced to ordinary differential system using adequate transformation. The obtained nonlinear system is then solved by Newton built-in shooting technique. Impacts of various physical parameters on entropy optimization, Bejan number, velocity, concentration and temperature are graphically examined. Numerical outcomes of gradients of velocity and temperature are discussed through tables via different physical variables. Entropy optimization rate has increasing effect for both Brinkman and Hartmann numbers, while opposite effect hold for Bejan number. Magnitudes of temperature and velocity boost up for higher estimation of curvature parameter and opposite effect is observed for concentration.