0
Research Papers: Forced Convection

A New Heat Transfer Correlation for Turbulent Flow of Air With Variable Properties in Noncircular Ducts

[+] Author and Article Information
Peng Wang, Zhiyun Wang

School of Energy and Power Engineering,
University of Shanghai for Science and Technology,
Shanghai 200093, China

Mo Yang

School of Energy and Power Engineering,
University of Shanghai for Science and Technology,
Shanghai 200093, China
e-mail: yangm@usst.edu.cn

Yuwen Zhang

Department of Mechanical
and Aerospace Engineering,
University of Missouri,
Columbia, MO 65211

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received May 2, 2013; final manuscript received June 5, 2014; published online July 2, 2014. Assoc. Editor: Ali Ebadian.

J. Heat Transfer 136(10), 101701 (Jul 02, 2014) (8 pages) Paper No: HT-13-1225; doi: 10.1115/1.4027855 History: Received May 02, 2013; Revised June 05, 2014

Turbulent flow and heat transfer of air with variable properties in a set of regular polygonal ducts and circular tube have been numerically simulated. All the ducts have the same hydraulic diameter as their characteristic lengths in the Reynolds number. The flow is modeled as three-dimensional (3D) and fully elliptic by using the finite volume method and the standard k-ε turbulence model. The results showed that the relatively strong secondary flow could be observed with variable properties fluid. For the regular polygonal ducts, the local heat transfer coefficient along circumferential direction is not uniform; there is an appreciable reduction in the corner region and the smaller the angle of the corner region, the more appreciable deterioration the corner region causes. The use of hydraulic diameter for regular polygonal ducts leads to unacceptably large errors in turbulent heat transfer determined from the circular tube correlations. Based on the simulation results, a correction factor is proposed to predict turbulent heat transfer in regular polygonal ducts.

FIGURES IN THIS ARTICLE
<>
Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Schematic diagram of the computational model

Grahic Jump Location
Fig. 2

Sample of computational mesh (not in scale)

Grahic Jump Location
Fig. 3

Comparison between the numerical results and those of previous investigations

Grahic Jump Location
Fig. 4

Variation of the local heat transfer coefficient versus the dimensionless ratio L/Dh

Grahic Jump Location
Fig. 5

Variation of the dimensionless axial velocity along the circular tube

Grahic Jump Location
Fig. 6

Regular hexagonal cross section velocity filed for variable properties fluid

Grahic Jump Location
Fig. 7

Regular hexagonal cross section velocity filed for constant properties fluid

Grahic Jump Location
Fig. 8

Distributions of the circumferential local heat transfer coefficient hy in the heated zone of the square duct

Grahic Jump Location
Fig. 9

Distributions of the circumferential local heat transfer coefficient hy for fully developed heat transfer of the ducts A-3, A-4, and A-6

Grahic Jump Location
Fig. 10

The proportion of the average Nusselt number for regular polygonal duct on that for circular tube Nu(An)/Nu(A−1) versus the number of sides of the ducts

Grahic Jump Location
Fig. 11

Comparison between the numerical results and the new correlation Eq. (16)

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In