Free Convective Thermal Transmission through Different Shapes of Enclosures: An Overview

Abstract:

Abstract. The topic of free convection thermal transmission through different geometrical shapes of enclosures is an engaging subject. It has caught the attention of the researchers during the last decades according to its significance in lots of engineering applications. Nuclear reactors, solar collectors, cooling electronic equipment, Oil wells, cooling electric components (as in the copper electric wires that are surrounded by the housing), and many industrial systems. Many parameters are discussed and analyzed to see their effect on the process of transferring heat such as: the effect of the geometrical shape, Nusslet number, and Rayliegh number. The studies were divided into seven categories based on the geometrical shape of the enclosure ( square , triangular, circular, trapezoidal, polygonal, elliptical, and wavy). The governing equations of the free convective thermal transmission were stated. The objective of this study is to collect the data from a large number of previous studies and compare them to reach a conclusion about the best results.

• Periodical: Defect and Diffusion Forum (Volume 449)
• Pages: 73-100
• DOI: https://doi.org/10.4028/p-4eONhz
• Online since: March 2026
• Authors: Abrar Al-Hadad*
• Keywords: Circular, Enclosure, Free Convection, Polygonal, Thermal Transmission, Triangular

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