Natural convection and heat transfer in Newtonian and non Newtonian fluids

Abstract

Over the years, the investigation of the sensitivity of temperature distribution and heat newlineand matter transport rates in natural convective Newtonian and non-Newtonian fluids newlinein the enclosure has gained considerable importance due to extensive applications in newlineindustries and cutting-edge innovation. Several works have appeared in the literature newlineconcerning natural convection, heat, and mass transfer in a closed domain with newlinedifferent shapes and boundary conditions. newlineIn the present study on the natural convection fluid flow and heat and mass newlinetransfer in an enclosure, various problems under different physical configurations are newlineconsidered for the computation of flow fields and the rate of heat and mass transfers. newlineThe governing equations of the flow are the conservation of mass, momentum, energy, newlineand concentrations supported by initial and boundary conditions. The finite element newlineGalerkin weighted residual method, in association with the Newton-Raphson scheme, newlineis used to solve the system of coupled equations. The sensitivity analysis on the newlinerate of heat and mass transfers concerning the flow and geometrical parameters is newlineperformed using the response surface method. newlineIn the first part of the thesis, we considered a natural convection flow of Newtonian newlinefluid in a two-dimensional inclined trapezoidal cavity filled with a porous newlinemedium interested in the underground spread of contaminations, atomic waste, and newlinesolar power collectors. The convection inside the trapezoidal enclosure is doublediffusive newlinedue to the difference in heat and mass concentration diffusions. One of newlinethe lateral walls of the chamber is imposed with a higher constant temperature and newlineconcentration, and the other vertical wall is maintained with a lower temperature and newlineconcentration. The top border is assumed to be insulated and permeable, while the enclosure s newlinebottom wall is subject to exponential varying temperature and concentration.