Pergamon
Int. Comm. Heat Mass Transfer, Vol. 26, NO. 6, pp. 869-878, 1999
Copyright © 1999Elsevier ScienceLtd
Printed in the USA. All rights reserved
0735-1933/99/S-see front matter
PH S0735-1933(99)00075-5
SIMULATION OF TURBULENT FLOW AND
HEAT TRANSFER AROUND RECTANGULAR BARS
Alvaro Valencia and Carolina Orellana
Department of Mechanical Engineering
Universidad de Chile
Casilla 2777, Santiago
CHILE
(Communicated by J.P. Hartnett and W.J. Minkowycz)
ABSTRACT
Numerical investigations on the turbulent fluid flow and the local heat transfer from
rectangular bars for three different aspect ratios were carried out with Re=22000 and Pr=-0.71.
The standard k-e turbulence model and a modified version were used in conjunction with the
Reynolds-averaged momentum and energy equations for the simulations. The predictions of
drag, lift, local and global heat transfer coefficients on the front, side and on the rear face of
the rectangular bars are compared with available experimental results.
© 1999 Elsevier Science Ltd
Introduction
The flow past slender, bluff structures is frequently associated with periodic vortex shedding causing
dynamic loading on the structures. For the design of such structures, the unsteady loading forces must be
known and hence methods for predicting the flow and the forces are of great practical importance.
Rectangular bar is also one of the most interesting bluff body in connection with the question of heat
transfer mechanism in the separated, reattached flow region. For situations with high Reynolds numbers,
which usually occur in practice, stochastic three-dimensional turbulent fluctuations are superimposed on
the periodic vortex-shedding motion. A resolution of these motions in a direct simulation is not feasible
at present. Hence, there is still a need for economic calculation methods based on the use of a turbulence
model for simulating the influence of the stochastic fluctuations on the periodic vortex-shedding motion.
Measurements of the velocity characteristics for the turbulent flow around a square cross-section bar
mounted in a water channel for Re=14000 show that in the zones of highest velocity oscillations the
energy associated with the turbulent fluctuations is about 40% of the total energy, [1]. Franke and Rodi
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