Comparative Analysis of two Non-Newtonian Fluid Models for a Stretching Cylinder

Abstract

The aim of the thesis is to demonstrate comparative analysis of two non-Newtonian fluid models such as Cross viscosity model and Carreau viscosity model. These models are significant for both low and high shear rate regions. The problem of only Cross viscosity model is established to examine heat source in unsteady, MHD nanofluid flow subject to convective boundary condi tions past a stretching cylinder incorporated with variable thermal properties. A mathematical model for comparison of both fluids with constant thermal properties are employed for analysis. In transforming governing partial differential equations into ordinary differential equations, sim ilarity variables are utilized that possesses a non-similar solution. The numerical solutions are found utilizing MATLAB package bvp4c. The velocity, temperature and concentration curves for various parameters are plotted graphically. The values for the coefficient of skin friction, heat transfer rate, mass transfer rate and micro-organisms local density for various choices of parameters are correspondingly tabulated. It is found that, in absolute sense Carreau nanofluids experience higher drag force in comparison to Cross nanofluids with effect of rising parameters like magnetic, porosity, Weissenberg, unsteadiness, temperature buoyancy and concentration buoyancy parameter. Moreover, there is smaller gyrotactic micro-organisms local density for Carreau fluids in comparison to Cross fluids.