Numerical Study of turbulent free convection of liquid metal with constant and variable properties in the presence of magnetic field

Document Type : Full Lenght Research Article

Author

Islamic Azad University, Pardis Branch

Abstract

In this research, turbulent MHD convection of liquid metal with constant and variable properties is investigated numerically. The finite volume method is applied to model the fluid flow and natural convection heat transfer in a square cavity. The fluid flow and heat transfer were simulated and compared for two cases constant and variable properties. It is observed that for the case variable properties in high Hartmann numbers (Ha) the temperature slope near the hot wall is more than the cold wall. For both cases, the temperature gradient near the hot and cold walls is high. By applying magnetic field and increasing the Ha the temperature slope reduces so at Ha=800 the profile is linear. In the case constant properties, the slope of temperature profile near the vertical walls is the same and the temperature profiles pass from one point at the center of the cavity. However,in the case variable properties as it was expected the temperature profile doesn’t pass one point and the slope of temperature profile at high Hartmann numbers near the hot and cold walls is partly different. Furthermore, it is indicated that for the case constant properties the Nusselt number is less than the case variable properties.

Keywords

dor 20.1001.1.2345508.2019.6.2.4.5

Main Subjects


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