Effect of wavy wall location on the natural convection in an enclosure containing a concentric heated circular cylinder

الملخص EN

An investigation has been made to study numerically the effect of wavy wall locations on natural convection flow in a two dimensional enclosure filled with air containing a concentric heated circular cylinder.

The external walls of the considered enclosure are maintained at a constant cold temperature (Tc) while the surface of the circular cylinder is kept at a constant hot temperature (Th).

The numerical simulation, based on a finite element approach, is performed using program ANSYS version 11.

The governing equations with boundary conditions are solved iteratively using the Tri-Diagonal Matrix Algorithm (TDMA).

The current work is validated with previous numerical results available in the literature.

The study aims to determine the effect of wavy wall location which is represented by varying the inclination angle (∅=0°, 90° and 180°), and undulation numbers (n=1 and 2) on flow field and heat transfer for four selected Rayleigh numbers (Ra=103 , 104 , 105, and 106).

Streamline and isotherm contours are determined.

The effect local Nusselt number along the hot surface of the circular cylinder is also examined in this study.

The results indicated that the average Nusselt number at the hot surface of the cylinder increases with increasing the Rayleigh numbers and reduces when undulation number increases from one to two.