Journal of Applied Science and Engineering

Published by Tamkang University Press


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N. Nithyadevi1, V. Divya This email address is being protected from spambots. You need JavaScript enabled to view it.1 and M. Rajarathinam1

1Department of Mathematics, Bharathiar University, Coimbatore - 641 046, India


Received: May 24, 2016
Accepted: January 31, 2017
Publication Date: June 1, 2017

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The present numerical study investigates the laminar natural convection heat transfer and the effect of Prandtl number in a two dimensional rectangular enclosure with discrete heaters. Four different cases are considered based on the number of discrete heaters which is maintained at isothermal condition Th (Th > Tc). The right vertical wall is maintained at cold temperature Tc and the remaining all other walls are thermally insulated. The above schematic setup can be modeled into mathematical form and the governing non-dimensional equations are solved using Finite Volume Method with power-law scheme. SIMPLE algorithm is employed for the pressure-velocity coupled momentum equations. Numerical simulations are carried out to find the effect of different Prandtl numbers (0.054, 0.71, 1.4 and 7.0), internal heat generation parameter Ri ranging from 0.1 to 10.0 and the distribution of discrete heaters. Results are given in the form of streamlines, isotherms, the velocity profiles and average Nusselt number. It is found that the maximum heat transfer rate is achieved for the distribution of discrete heater and also for increasing values of Prandtl number.

Keywords: Discrete Heater, Natural Convection, Prandtl Number, SIMPLE Algorithm


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