Thermal and entropy generation analysis of hybrid nanofluid flow through stretchable rotating system with heat source/sink

This study presents the thermal-fluid transport and entropy generation of a hybrid nanofluid consisting of titanium oxide(TiO2) and gallic oxide(GO), flowing past a stretchable rotating system with a heat source/sink subjected to nonlinear radiation. The nanofluid transport past the rotating disk embedded in a porous medium is described utilizing a higher-order partial nonlinear coupled differential model simplified into an ordinary nonlinear model utilizing Karman's transformation. This is analyzed utilizing the fourth fifth-order Runge Kutta Fehlberg method (RKF-45) and validated against other literatures for a simple condition that proves satisfactory. The analysis illustrates the impact of nanoparticle volume concentration on entropy generation. This shows that the increasing volume of nanoparticles concentration increases entropy, with the entropy of the hybrid nanofluid lower in relation to the nanofluid. At volume concentration of nanoparticles 0 < phi < 0.2 reveals an entropy magnitude of 7J/K at the lower disk, as the fluid approaches mid plate entropy steadily drops to 3J/K. Thereafter, the magnitude of entropy - as the nano mixture approaches the upper disk - steadily rises to 8J/K. The effect of nanoparticle volume concentration further depicts an increase in Bejan's number. The study provides good insight into useful and practical applications, including turbines, power generating systems, and blood centrifuges, among others.