# A NUMERICAL STUDY ON MHD NATURAL CONVECTIVE HEAT TRANSFER IN AN AG-WATER NANOFLUID FILLED ENCLOSURE WITH CENTER HEATER

• NITHYADEVI, N. (DEPARTMENT OF MATHEMATICS, BHARATHIAR UNIVERSITY) ;
• MAHALAKSHMI, T. (DEPARTMENT OF MATHEMATICS, BHARATHIAR UNIVERSITY)
• Accepted : 2017.12.10
• Published : 2017.12.25

#### Abstract

The natural convective nanofluid flow and heat transfer inside a square enclosure with a center heater in the presence of magnetic field has been studied numerically. The vertical walls of the enclosure are cold and the top wall is adiabatic while the bottom wall is considered with constant heat source. The governing differential equations are solved by using a finite volume method based on SIMPLE algorithm. The parametric study is performed to analyze the effect of different lengths of center heater, Hartmann numbers and Rayleigh numbers. The heater effectiveness and temperature distribution are examined. The effect of all pertinent parameters on streamlines, isotherms, velocity profiles and average Nusselt numbers are presented. It is found that heat transfer increases with the increase of heater length, whereas it decreases with the increase of magnetic field effect. Furthermore, it is found that the value of Nusselt number depends strongly upon the Hartmann number for the increasing values of Rayleigh number.

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