Entropy analysis for comparative study of effective Prandtl number and without effective Prandtl number via γAl2O3-H2O and γAl2O3-C2H6O2 nanoparticles

We investigate entropy generation optimization regarding heat source/sink in nonlinear radiative flow over a stretched surface. Thermodynamic second law is invoked in mathematical modeling. Effective Prandtl number model has been used to examine the characteristics of viscous nanomaterial flow with entropy generation. Considered nanoparticles are (gamma A(l)2O(3)-H2O and gamma Al2O3-C2H6O2). Viscous dissipation and mixed convection are also examined. An optimal homotopy technique leads to solutions development. Optimal values of auxiliary parameters are calculated. Comparison between effective Prandtl number and without effective Prandtl is investigated. Total entropy generation rate is obtained. It is examined from obtained results that velocity is increased by higher estimation of nanoparticle volume fraction. Temperature reduces for higher rate of nanoparticles volume fraction in case of effective Prandtl number while opposite behavior is observed for without effective Prandtl number. Here, entropy generation strongly depends upon values of Brinkman number, radiation and temperature ratio parameter. Impacts of radiation and Brinkman number on Bejan number are quite reverse. Main conclusions are presented in concluding remarks. (C) 2018 Elsevier B.V. All rights reserved.