HEAT TRANSFER BEHAVIOR OF NON-NEWTONIAN CARREAU FLUID BETWEEN ROTATING CONCENTRIC VERTICAL CYLINDERS

摘要

Laminar flow and heat transfer mechanism of a non-Newtonian fluid in the annular space between two coaxial rotating cylinders is analyzed. The problem is considered when the inner cylinder rotates about the common axis with constant angular velocity and the outer cylinder at the rest. The horizontal endplates are assumed adiabatic. The Carreau stress-strain constitutive equation was adopted to model the rheological fluid characteristics. The governing equations are numerically solved by a time-marching finite element algorithm. It is employed to compute numerical solution through a semi-implicit Taylor-Galerkin/pressure-correction scheme, based on a fractional-step formulation. The effect of rheological parameters on the heat transfer and on the flow is investigated. The results of natural, forced and mixed convections are presented and discussed.