Title: Evolutionary design investigation applied to mixed convection heat transfer flows over semi-elliptical blocks inserted into a rectangular channel

Authors: Andre Luis Razera; Roberta Juliana Collet da Fonseca; Liércio André Isoldi; Elizaldo Domingues dos Santos; Luiz Alberto Oliveira Rocha; Cesare Biserni

Addresses: Graduate Program of Ocean Engineering, School of Engineering, Federal University of Rio Grande (FURG), Italia Avenue, Km 8, Rio Grande, RS, Brazil ' Department of Mechanical Engineering, Federal University of Rio Grande do Sul (UFRGS), 425, Sarmento Leite Street, Porto Alegre, RS, Brazil ' Graduate Program of Ocean Engineering, School of Engineering, Federal University of Rio Grande (FURG), Italia Avenue, Km 8, Rio Grande, RS, Brazil ' Graduate Program of Ocean Engineering, School of Engineering, Federal University of Rio Grande (FURG), Italia Avenue, Km 8, Rio Grande, RS, Brazil ' Graduate Program of Ocean Engineering, School of Engineering, Federal University of Rio Grande (FURG), Italia Avenue, Km 8, Rio Grande, RS, Brazil; Department of Mechanical Engineering, Federal University of Rio Grande do Sul (UFRGS), 425, Sarmento Leite Street, Porto Alegre, RS, Brazil ' Department of Industrial Engineering (DIN), Alma Mater Studiorum – University of Bologna, Bologna, Italy

Abstract: This numerical manuscript focuses on the constructal design of a system characterised by mixed convection heat transfer flows over the heated semi-elliptical devices installed into a horizontally oriented channel. The primary aim of this study is to increase the heat transfer rate and decrease the pressure drop in the system by changing the two blocks' geometry. The constraints, degrees of freedom, and performance metrics are chosen according to the constructal design method. The technique for order preference by similarity to the ideal solution method evaluates the multi-objective problem. By comparing the best and worst shapes, an increase of 40% for the thermal and 703% for fluid dynamic performances is noticed in the second optimisation level. Also noteworthy is the importance of evaluating different arrangements of the blocks within the channel, and the difference in performance obtained is up to 40% for the thermal and 12% for the fluid dynamic cases, respectively. In the multi-objective viewpoint, the above-cited method allowed the achievement of recommendations for designing the intruded fins, considering several scenarios where the fluid dynamic and thermal purposes are more or less dominant.

Keywords: elliptical blocks; mixed convection; constructal design method; cooling; TOPSIS method.

DOI: 10.1504/IJHM.2024.140567

International Journal of Hydromechatronics, 2024 Vol.7 No.3, pp.196 - 223

Received: 25 Dec 2023
Accepted: 10 Feb 2024
Published online: 23 Aug 2024 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article