Numerical investigation of natural convection phenomena in uniformly heated trapezoidal Cylinder inside an elliptical Enclosure

A numerical study of the natural convection of the laminar heat transfers in the stationary state was developed in a horizontal ring and compared between a heated trapezoidal internal cylinder and a cold elliptical outer cylinder. This annular space is traversed by a Newtonian and incompressible fluid. The Prandtl number is set to 0.7 (air case) for different Rayleigh numbers. The system of equations governing the problem was solved numerically by the calculation code Fluent based on the finite volume method. In these simulations the Boussinesq approximation was considered. The inner and outer surfaces are kept at a constant temperature. The study is performed for Rayleigh numbers ranging from 103 to 105. Indeed, the effects of different numbers of thermal Rayleigh on natural convection were studied. The results are presented in the form of isotherms, isocurrents, local and average numbers of Nusselt. The purpose of this study is to study the influence of the thermal Rayleigh number, and the change of the angle of inclination of the trapezoidal lateral walls on the structure of the flow and the distribution of the temperature.