Three-dimensional analysis of heat transfer and entropy production of jet impingement hybrid nanofluid cooling a porous media-filled heat sink

ABSTRACT

In this study, a numerical assessment was carried out on heat transfer and entropy production of a three-dimensional heat sink exposed to an impinging jet, where the area between the heat sink fins is filled with aluminum foam saturated with $\mathrm{A}{\mathrm{L}}_2{\mathrm{O}}_3-\mathrm{C}\mathrm{u}/\mathrm{w}\mathrm{a}\mathrm{t}\mathrm{e}\mathrm{r}$ hybrid nanofluid. Darcy-Brinkman-Forchheimer’s model with the local thermal equilibrium was considered. The effects of various important parameters such as Reynolds number $\left(400\le \mathrm{R}\mathrm{e}\le 1600\right)$, volumetric concentrations $\left(1\mathrm{\%}\le {\phi }_{hnf}\le 5\mathrm{\%}\right)$, Darcy number $\left({10}^{-5}\le \mathrm{D}\mathrm{a}\le {10}^{-1}\right)$, porosity $\left(0.1\le \epsilon \le 0.6\right)$, and the diameter of nanoparticles $\left(20\mathrm{n}\mathrm{m}\le \mathrm{d}\mathrm{n}\le 60\mathrm{n}\mathrm{m}\right)$ on fluid flow, heat transfer, drop pressure, and entropy generation were investigated. A finite-volume approach with SIMPLE algorithm was employed to solve continuity, momentum, energy, and entropy equations with the help of the Ansys-Fluent 14.5 program. Regarding the validation of the computational approach used in this paper, a strong consensus has been reached with other findings available in the literature. Outcomes indicated that boosting Darcy number $\left(\mathrm{D}\mathrm{a}\right)$ and porosity $\left(\epsilon \right)$ of the used porous material helps increase the heat exchange rate by up to $72\mathrm{\%}$ and $40\mathrm{\%}$, respectively. On the other hand, we obtained a $7\mathrm{\%}$ enhancement in the heat transmission rate when using nanoparticles with a diameter $\left(\mathrm{d}\mathrm{n}\right)$ of $20\mathrm{n}\mathrm{m}$ instead of nanoparticles with a diameter of 60 nm. Furthermore, it has been demonstrated that boosting $\mathrm{D}\mathrm{a}$, $\epsilon$ and $\mathrm{d}\mathrm{n}$ minimize drop pressure by various proportions. Based on the entropy production analysis, it is possible to infer that entropy due to heat transfer is more dominant than other types of entropy with all parameters analyzed. Also, it can be deducted that as the values of $\epsilon$ and $\mathrm{D}\mathrm{a}$ grow and the values of $\mathrm{d}\mathrm{n}$ decline, the total entropy production $(S_{p,t})$ rises up to $55\mathrm{\%}$, $75\mathrm{\%}$ and $3\mathrm{\%}$, respectively. The same findings were reached with the Bejan number $\left(\mathrm{B}\mathrm{e}\right)$, but different percentages. Finally, three correlations of Nusselt number with several variables with an error not exceeding $15\mathrm{\%}$ have been suggested. The proposed study’s findings may be utilized to define appropriate process factors for improved thermodynamic efficiency of heat sinks using hybrid nanofluids and porous media.

KEYWORDS:

• Impinging jet
• heat sink
• porous medium
• hybrid nanofluids
• entropy production

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Bouziane Boudraa

Bouziane Boudraa is a PhD student in mechanical engineering at mentouri brothers university of constantine 1, Algeria. His specialties include heat transfer, laminar and turbulent flow, impinging jet, nanofluids, hybrid nanofluids, porous media, heat sink and magnetic field.

Rachid Bessaïh

Rachid Bessaïh is a professor at mentouri brothers university of constantine 1, Algeria. His research focuses on forced and natural convection, nanofluid, heat and mass transfer, porous media, entropy generation, electronic components and magnetic field.