Arash Karimipour ¹, Seyed Sadegh Mirtalebi ¹, Masoud Afrand ¹

Affiliations
1 Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Isfahan, IR

Abstract

In this study, using the finite volume method, a numerical investigation on mixed convection flow and heat transfer in a two-sided lid-driven shallow cavity which is subjected to Al₂O₃-water nanofluid was applied. The study was conducted in different velocity ratio and the mean particle diameter is 80 nm. Thermal conductivity and dynamic viscosity of above mentioned nanofluid were calculated by utilizing H-C and Jang models, respectively. The impact of different ratio of velocity at the particular Richardson number of the nanofluid is discussed, with respect to hydrodynamic and thermal characteristics. The results declared great enhancement in heat transfer by increasing the velocity ratio. Besides, it can be points out that heat transfer enhanced considerably by addition of Al₂O₃ nanoparticles compared with that of the water.

Keywords

Al₂O₃-water, Heat Transfer, Isotherm Lines, Shallow Square Enclosure, Streamline

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Arash Karimipour ¹, Habibollah Alipour ², Omid Ali Akbari ², Davood Toghraie Semiromi ², Mohammad Hemmat Esfe ¹

Affiliations
1 Department of Mechanical Engineering, Najafabad Branch, Islamic Azad University, Isfahan, IR
2 Department of Mechanical Engineering, Khomeinishahr Branch, Islamic Azad University, Khomeinishahr, IR

Abstract

The purpose of this study is to investigate the influence of indentations on the parameters of fluid flow and heat of water-silver nanofluid in a rectangular two-dimensional micro channel. It includes heat transfer water silver nano fluid in an indented micro channel under the constant temperature. The system is numerically modeled, by Finite Volume Method. After solving the governing equations for U, V and θ, other useful quantities such as Nusselt number and friction factor can be determined. The hot fluid inlet exits after cooling by the cold walls of the micro channel. Calculations are done for the two ranges of Reynolds number (Re). It was observed that at times the fluid has more indentations; it has a greater temperature drop that is at the output cross section of the micro channel. With increasing Reynolds number (Re), number of the indentations and the increasing volume fraction of the nanoparticles, greater temperature drop occurs. The presence of indentation in the micro channel increases the speed and the dimensionless temperature at the center line. Finally, the results are provided in the form of the contour of flow and isothermal lines, the coefficient of friction, Nusselt number, temperature and velocity profiles in different micro channel sections. The results of the numerical simulation indicate that the heat transfer rate is significantly affected by the solid volume fraction and Reynolds number.

Keywords

Heat Transfer, Local Friction Factor, Nanofluid, Nusselt Number, Rib Micro Channel

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