Analytical Solutions for Boundary Layer Flows of Differential Type Fluids

Abstract

The study of unsteady flow and heat transfer of non-Newtonian fluids over stretching surface is very important and serves a widespread variety of practical applications in industry. In this thesis, a theoretical study is undertaken into fluid flow and heat transfer due to stretching surface for the non-Newtonian second grade fluid. The second grade fluid considered in the current analysis is a subclass of differential type nonlinear fluid. Additionally, second grade liquid is capable to explore the features of normal stress impacts. More specifically, this thesis is concerned with study of the unsteady boundary layer flow and heat transfer characteristics for a second grade liquid over stretching surface and considered different problems of practical interest. The problems include, the forced convective heat transfer over stretching surface assuming different situations including nanolfuid, chemical processes and Cattaneo-Christov heat and mass flux relations. The transformed boundary layer equations are solved analytically by the homotopy analysis method. The analytical solutions have been computed for the velocity, temperature and concentration distributions. The effects of important physical parameters are presented graphically in order to visualize the impact of these parameters. The effects of non-dimensional parameters on the temperature, concentration and local Nusselt are elaborated through graphs and tables. The effect of non-dimensional parameters on the local Nusselt is discussed by using graphs. The obtained results reveal that the temperature profile diminishes for augmented values of the thermal relaxation parameter. In addition to this, it has come to the observation that the liquid temperature is higher for classical Fourier's law when compared to non- Fourier's law. It is estimated from the plots that the concentration of the second grade nanoliquid drops as the Brownian motion parameter increases while the reverse trend is detected for the thermophoresis parameter. Moreover, it is perceived from the results that the temperature of the second grade nanoliquid declines as unsteadiness parameter enhances.