Table of Contents
ISRN Mechanical Engineering
Volume 2011, Article ID 932738, 13 pages
http://dx.doi.org/10.5402/2011/932738
Research Article

Unsteady Heat Transfer from an Equilateral Triangular Cylinder in the Unconfined Flow Regime

Department of Chemical Engineering, Indian Institute of Technology Roorkee, Uttarakhand 247 667, India

Received 14 January 2011; Accepted 14 February 2011

Academic Editors: H. Hadavinia, F. H. Moukalled, and S. C. M. Yu

Copyright © 2011 Amit Dhiman and Radhe Shyam. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Effects of Reynolds number on the heat transfer characteristics of a long (heated) equilateral triangular cylinder are investigated for the range of conditions Re = 50–150 (in the steps of 10) and Prandtl number = 0.71 (air) in the unconfined unsteady cross-flow regime. In order to simulate the present situation, the computational grid is created by using commercial grid generator GAMBIT and the numerical computations are carried out by using FLUENT (6.3). The SIMPLE method is used to solve continuity, Navier-Stokes and energy equations along with the appropriate boundary conditions. The second order upwind scheme is used to discretize the convective terms, while the central difference scheme is used to discretize the diffusive terms in the governing equations. The present results are in an excellent agreement with the literature values. The temperature isotherms and temporal history of Nusselt number are presented in detail. The local as well as time-averaged Nusselt numbers are calculated. The time-averaged Nusselt number increases with increasing Reynolds number for the fixed value of the Prandtl number. Finally, the present numerical results are used to develop the simple heat transfer correlation for the range of conditions covered here.