Effects of cavity and heat source aspect ratios on natural convection of a nanofluid in a C-shaped cavity using Lattice Boltzmann method

Abstract

Purpose The purpose of this paper is to consider natural convection of a nanofluid inside of a C-shaped cavity using Lattice Boltzmann method (LBM). Design/methodology/approach Effects of some geometry and flow parameters consisting of the aspect ratio of the cavity, aspect ratio of the heat source; Rayleigh number (Ra = 103 − 106) have been investigated. The validity of the method is checked by comparing the present results with ones from the previously published work. Findings The results demonstrate that for Ra = 103, the aspect ratio of the heat source has more influence on the average Nusselt number in contrast to the case of Ra = 106. Contrary to the fact that the average Nusselt number increases non-linearly more than twice because of the increase of the aspect ratio of the enclosure at Ra = 103, the average Nusselt number has a linear relation with the aspect ratio for of Ra = 106. Therefore, upon increasing the Rayleigh number, the efficiency of the aspect ratio of the cavity on the thermal convection, gradually diminishes. Originality/value The authors believe that all the results, both numerical and asymptotic, are original and have not been published elsewhere.

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Free Convection of Hybrid Nanofluids in a C-Shaped Chamber under Variable Heat Flux and Magnetic Field: Simulation, Sensitivity Analysis, and Artificial Neural Networks

“…It should be noted that the third and fourth terms in the right part of Equations (6) and 7describe the influence of the inclined magnetic field (the third term is an inclined magnetic field effect, where the magnetic field inclination angle is α) and inclined gravity force (the forth term characterizes an effect of the cavity inclination, where the cavity inclination angle is α).…”

“…Nanofluids were first prepared by Choi in 1995 [1]. Since then, they have been considered by many researchers in engineering and heat transfer applications owing to their improving heat transfer properties [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. For the stable distribution of nanoparticles in the closed chambers, energy transport can be essentially improved compared to the absence of nanoparticles (i.e., base fluid only).…”

Effects of rotation angle and metal foam on natural convection of nanofluids in a cavity under an adjustable magnetic field

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