Effect of nanoparticle shape on natural convection heat transfer in a square cavity with partitions using water-SiO2 nanofluid

Document Type: Original Research Paper

Authors

1 Associate professor, Department of Mechanical Engineering, University of Kashan, Iran

2 Young Researchers and Elite Club, Arak Branch, Islamic Azad University, Arak, Iran

3 MSc student, Department of Mechanical Engineering, University of Kashan, Iran

Abstract

In this paper a numerical investigation is performed to study the effects of different nanofluids on convective heat transfer enhancement in a partitioned square cavity subject to different shapes of nanoparticle using water-SiO2 nanofluid. This study has been carried out to analyze the effects of SiO2 nanoparticle, its volumetric fraction between 2 and 4%, and nanoparticle shape (i.e. blades, platelets, cylindrical, bricks, and spherical), on the fluid flow and heat transfer characteristics. The overall continuity, momentum, and energy equations are solved by using the finite-volume method and the SIMPLE algorithm. The influence of related parameters such as Rayleigh number (Ra=105 to 107) and height of partition (h=0.1, 0.3, 0.5H) are studied. Based on the results, independent of nanoparticle shape, the streamlines and isotherms are extremely affected by Rayleigh number and height of partition. For a fixed amount of the partition height, average Nusselt number increases as the Rayleigh number rises.

Keywords