Eur. Phys. J. Plus (2021) 136: 700
https://doi.org/10.1140/epjp/s13360-021-01623-5

Regular Article

A novel metaheuristic combinatorial algorithm to optimize the natural convection across a vertical enclosure divided by perforated flat horizontal louvers inside

Mechanical Engineering Department, Razi University, Kermanshah, Iran

^b Veysi_farzad@yahoo.com

Received: 20 March 2021
Accepted: 29 May 2021
Published online: 29 June 2021

Abstract

The natural convection across a divided enclosure is an ongoing attractive research topic due to its occurrence in various thermal applications, which can be utilized as a dual-purpose application to suppress or enhance the heat transfer. In this investigation, a vertical divided enclosure is introduced by a modified configuration in which the enclosure is divided by perforated adiabatic flat horizontal louvers. The circular perforations are also arranged along the louvers. Then, the natural convection across the modified divided enclosure is experimentally investigated versus design parameters. Different constant temperatures are exerted to the side walls of the enclosure, while other walls are kept non-heated. The design parameters are the Rayleigh number (7 × 10³ ≤ Ra ≤ 1.45 × 10⁴), louver’s slant angle (0° ≤ φ ≤ 150°), perforation’s diameter to louver’s width ratio (0.2 ≤ d/w ≤ 0.6) as well as enclosure’s aspect ratio (7.8723 ≤ Ar ≤ 9.3671). After that, a mathematical correlation is extracted for the mean Nusselt number (Nu_m) versus the design parameters. In the following, the teaching–learning-based optimization algorithm and wingsuit flying search optimization algorithm are combined in the frame of a novel combinatorial optimization algorithm. The combinatorial algorithm is then employed to optimize the obtained mathematical correlation. It was reported that the maximum heat transfer corresponds to the highest level of the Rayleigh number, d/w ratio as well as Ar. Moreover, for the minimum heat transfer, the Rayleigh number, d/w ratio as well as Ar, must be at the lowest level. The maximum and minimum heat transfers both occur at the same critical value of the louver’s angle (φ_crit ≈ 90°).