Constructal design of high-emissivity radiation inserts embedded in a disk-shaped heat generation body

This study documents geometrical optimization of inserts with high-emissivity applied for cooling a disk shaped body with heat generation based on constructal theory. The high-emissivity inserts used for cooling purposes are located in radial direction in three structures: radial structure, radial structure with one level of discontinued pairing and radial structure with two levels of discontinued pairing. An analytical method is proposed for calculating the maximum temperature of the disk which is verified by the numerical results of a commercial program. The aim of design and optimization is obtaining the best configuration so that thermal resistance is minimized. The degrees of freedom are the radius of pairing the aspect of inserts' thickness. Results show that the percentage of area which is allocated to high-emissivity inserts has the most significant effect on thermal resistant. Secondly, the factor that affects the maximum temperature of the disk is number of inserts in center of the disk. In other word, increasing the high emissivity area and number of inserts lead to reduction of the thermal resistance. Moreover, by evaluating the results, it is apprehended that by adding pairing to the structure even in same number of inserts the thermal resistance reduced significantly. (C) 2016 Published by Elsevier Ltd.