Simultaneous optimization of inclination angle and fin characteristics on heat transfer in a rectangular enclosure

Abstract

This paper examines the prospect of increasing or decreasing the heat transfer through a rectangular enclosure with an aspect ratio of 2 in two Rayleigh numbers 105 and 106 by optimizing its inclination angle and the parameters of a highly conductive thin fin attached to its hot surface. The enclosure is heated from below, and the dominant heat transfer mechanism within the enclosure is the free convection. Optimization is performed by particle swarm optimization algorithm. The equations of energy, continuity, and momentum for free convection heat transfer in the enclosure are discretized by the finite volume method and are numerically solved. The optimization objective is to adjust the enclosure inclination angle and the fin parameters (position and height), so that heat transfer into the cold wall becomes minimized or maximized. The attained results reveal that the heat transfer through such an enclosure can be increased significantly up to 23% by its inclination angle 20.6° and the addition of a thin fin at the optimal location 0.72 and optimal height 0.2 in Rayleigh 106. Also, the obtained results show that heat transfer can be decreased up to 32% by the slight adjustment of its inclination angle 1.7° and addition of a thin fin at the optimal location 1.41 and optimal height 0.2 in Rayleigh number 105.