Numerical simulation of turbulent natural convection of nanofluid with thermal radiation inside a tall enclosure under the influence of magnetohydrodynamic

Abstract

In the present study, the natural convective heat transfer in the turbulent flow of water/CuO nanofluid with volumetric radiation and magnetic field inside a tall enclosure has been numerically investigated. The thermophysical properties of nanofluid have been considered variable with temperature and the effects of Brownian motion of nanoparticles have been considered. The main objective of this work is an investigation of the effect of using water/CuO nanofluid and presence of magnetic field on turbulent natural convection in three types of enclosures (vertical, inclined, and horizontal) by considering the volumetric radiation. The governing equations on turbulent flow domain under the influence of the magnetic field and by considering the combination of volumetric radiation and natural convection have been solved by a coupled algorithm. For validating the present research, a comparison has been carried out with the laminar natural convection flow under the influence of the magnetic field and radiation effects and also, the natural turbulent convection flow of previous studies and a proper coincidence has been achieved. The results indicated that by increasing volume fraction and Hartmann number the average Nusselt number enhances and reduces, respectively. By adding 1% CuO nanoparticles to the base fluid, heat transfer improves from 10.59% to 17.05%. However, by increasing the volume fraction from 1% to 4%, heat transfer improves from 1.35% to 4.90%. By increasing Hartmann number from 0 to 600, heat transfer reduces from 9.29% to 22.07%. Also, the results show that the ratio of deviation angle of the enclosure to the horizontal surface has considerable effects on heat transfer performance. Therefore, in similar conditions, the inclined enclosure with a deviation angle of 45° compared to the vertical and horizontal enclosure has better thermal performance.

Examining rheological behavior of CeO2-GO-SA/10W40 ternary hybrid nanofluid based on experiments and COMBI/ANN/RSM modeling

“…The proposed models can help to reduce the time and resources needed for experiments. Also, the models in the present study can be used in a variety of applications such as heat sinks [85][86][87] , heat pipes 88 , microchannels 89,90 , heat exchangers [91][92][93] , enclosures 94,95 , solar energy 9,96,97 and automotive industry [98][99][100][101] .…”

Turbulent natural-convection heat transfer in a square cavity with nanofluids in presence of inclined magnetic field

“…For the turbulent natural convection MHD, we find in the literature, a numerical investigation on the laminar and turbulent convection of pure water confined in a square enclosure subjected to the influence of a uniform horizontal magnetic field conducted by Sajjadi et al [9]. Another work on the transfer of heat by convection and radiation in a turbulent flow of a nanofluid (CuO-Water) subjected to the influence of a magnetic field, is carried out by Rahmati et al [10]. The results show that heat transfer improves with increasing volume fraction of nanoparticles and decreases with increasing Hartmann number.…”

Experimental study of exergetic performance of Al2O3 nanofluid in a double‐pipe heat exchanger fitted by a new modified twisted tape

“…Exergy is considered as a measure of the quality of energy and its extent of loss by irreversibility in a thermal system. One of the main applications of the exergy concept is the analysis of thermal systems using exergy balances 26‐28 . Exergy dissipation calculations of a transformation indicate the degree of nonreturn.…”

“…One of the main applications of the exergy concept is the analysis of thermal systems using exergy balances. [26][27][28] Exergy dissipation calculations of a transformation indicate the degree of nonreturn. Analyzing the effective parameters of this loss can help to understand the role of various factors and explain how they change the process so as to reduce nonreturn, increase efficiency, and ultimately optimize the process.…”