Yamuk Kesitli Kanal İçerisinde Hidrodinamik Olarak Tam Gelişmiş Isıl Olarak Gelişmekte Olan Laminer Akış ve Isı Transferinin Sayısal Olarak İncelenmesi

Year 2012, Volume: 9 Issue: 2, - , 01.04.2012

Nevzat Onur Kamil Arslan Oğuz Turgut

Abstract

In this study, steady-state hydrodynamically fully developed thermally developing
three-dimensional laminar forced convection flow and heat transfer in a horizontal
smooth trapezoidal duct were numerically investigated under uniform surface temperature
condition. Numerical study was carried out for a Reynolds number range of 100 to 1000. Air (P r ∼= 0.7) was used as the heat transfer medium. A commercial CFD program Fluent
12.1 was used to carry out the numerical study. Average Nusselt numbers and average
Darcy friction factors were presented for different Reynolds numbers. Local Nusselt numbers
were plotted as a function of the distance along the duct. Velocity and temperature
contours were given as graphically at different positions along the duct. The results obtained
from this study were compared with the results of similar studies available in the
literature, and the results were found to be in good agreement. It is seen that increase in
Reynolds number causes decrease in friction factor and increase in heat transfer. Value
of the Nusselt number for hydrodynamically and thermally fully developed laminar flow
conditions in trapezoidal cross-sectioned duct was determined to be 2.95. Based on the
present numerical investigation, new engineering correlations were obtained for the heat
transfer and friction coefficient.

Keywords

Trapezoidal cross-section duct, laminar forced convection, hydrodynamically fully developed thermally developing flow, Ansys Fluent 12.1.

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