0
Research Papers

Novel Jet Impingement Cooling Geometry for Combustor Liner Backside Cooling

[+] Author and Article Information
E. I. Esposito

 Lockheen Martin Space Systems Company, New Orleans, LA 70734

S. V. Ekkad1

Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061sekkad@vt.edu

Yong Kim, Partha Dutta

 Solar Turbines, Inc., San Diego, CA 92101

1

Corresponding author.

J. Thermal Sci. Eng. Appl 1(2), 021001 (Aug 20, 2009) (8 pages) doi:10.1115/1.3202799 History: Received October 21, 2008; Revised April 28, 2009; Published August 20, 2009

Impinging jets are commonly used to enhance heat transfer in modern gas turbine engines. Impinging jets used in turbine blade cooling typically operate at lower Reynolds numbers in the range of 10,000–20,000. In combustor liner cooling, the Reynolds numbers of the jets can be as high as 60,000. The present study is aimed at experimentally testing two different styles of jet impingement geometries to be used in backside combustor cooling. The higher jet Reynolds numbers lead to increased overall heat transfer characteristics, but also an increase in crossflow caused by spent air. The crossflow air has the effect of rapidly degrading the downstream jets at high jet Reynolds numbers. In an effort to increase the efficiency of the coolant air, configurations designed to reduce the harmful effects of crossflow are studied. Two main designs, a corrugated wall and extended port, are tested. Local heat transfer coefficients are obtained for each test section through a transient liquid crystal technique. Results show that both geometries reduce the crossflow induced degradation on downstream jets, but different geometries perform better at different Reynolds numbers. The extended port and corrugated wall configurations show similar benefits at the high Reynolds numbers, but at low Reynolds numbers, the extended port design increases the overall level of heat transfer. This is attributed to the developed jet velocity profile at the tube exit. The best possible explanation is that the benefit of the developed jet velocity profile diminishes as jet velocities rise and the air has lesser time to develop prior to exiting.

FIGURES IN THIS ARTICLE
<>
Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Experimental test rig

Grahic Jump Location
Figure 2

Mesh heater response

Grahic Jump Location
Figure 3

Temperature history of a single pixel

Grahic Jump Location
Figure 4

Corrugated wall impingement design

Grahic Jump Location
Figure 5

Uniform extended port geometry

Grahic Jump Location
Figure 6

Variable extended port geometry

Grahic Jump Location
Figure 7

Detailed Nusselt number distributions for Re=20,000

Grahic Jump Location
Figure 8

Detailed Nusselt number distributions for Re=40,000

Grahic Jump Location
Figure 9

Detailed Nusselt number distributions for Re=60,000

Grahic Jump Location
Figure 10

Comparison of area averaged Nusselt numbers for Re=20,000

Grahic Jump Location
Figure 11

Comparison of area averaged Nusselt numbers for Re=40,000

Grahic Jump Location
Figure 12

Comparison of span averaged Nusselt number distributions for Re=60,000

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