0
Research Papers

Effect of Flow Parameter Variations on Full Coverage Film-Cooling Effectiveness for a Gas Turbine Blade

[+] Author and Article Information
Shantanu Mhetras, Ron Rudolph

 Siemens Power Generation, Inc., 4400 Alafaya Trail, Orlando, FL 32826

Je-Chin Han

Department of Mechanical Engineering, Turbine Heat Transfer Laboratory, Texas A&M University, College Station, TX 77843-3123jc-han@tamu.edu

J. Turbomach 134(1), 011004 (May 24, 2011) (10 pages) doi:10.1115/1.4003228 History: Received April 13, 2010; Revised June 08, 2010; Published May 24, 2011; Online May 24, 2011

The effect of film-cooling holes placed along the span of a fully cooled high pressure turbine blade in a stationary, linear cascade on film-cooling effectiveness is studied using the pressure sensitive paint technique. The effect of showerhead injection at the leading edge and the presence of compound angled, diffusing holes on the pressure and suction sides are also examined. Six rows of compound angled shaped film-cooling holes are provided on the pressure side while four such rows are provided on the suction side of the blade. The holes have a laidback and fan-shaped diffusing cross-section. Another three rows of cylindrical holes are drilled at a typical angle on the leading edge to capture the effect of showerhead film coolant injection. The film-cooling hole arrangement simulates a typical film cooled blade design used in Stage 1 rotor blades for gas turbines used for power generation. An optimal target blowing ratio is defined for each film hole row, and tests are performed for 100%, 150%, and 200% of this target value. Tests are performed for inlet Mach numbers of 0.36 and 0.45 with corresponding exit Mach numbers of 0.51 and 0.68, respectively. The flow remains subsonic in the throat region for both Mach numbers. The corresponding freestream Reynolds numbers, based on the axial chord length and the exit velocity, are 1.3×106 and 1.74×106, respectively. Freestream turbulence intensity level at the cascade inlet is 6%. The results show that varying blowing ratios can have a significant impact on film-cooling effectiveness distribution. Large spanwise variations in effectiveness distributions are also observed. Similar distributions were observed for both Mach numbers.

FIGURES IN THIS ARTICLE
<>
Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Typical film-cooling blade design

Grahic Jump Location
Figure 2

Schematic of cascade with film cooled blade

Grahic Jump Location
Figure 3

Film-cooling blade with compound shaped holes

Grahic Jump Location
Figure 4

Bottom half of a 3D blade cut at midspan

Grahic Jump Location
Figure 5

Mach number distributions

Grahic Jump Location
Figure 6

Calibration curve for PSP: (a) PSP calibration normalized at a single reference temperature and (b) PSP calibration normalized at corresponding reference temperature

Grahic Jump Location
Figure 7

Optical component setup

Grahic Jump Location
Figure 8

Film-cooling effectiveness distributions for three blowing ratios at Main=0.36 with showerhead ejection

Grahic Jump Location
Figure 9

Film-cooling effectiveness distributions for three blowing ratios at Main=0.36 without showerhead ejection

Grahic Jump Location
Figure 10

Effect of blowing ratio on spanwise average film-cooling effectiveness distributions at Main=0.36 with and without showerhead ejection

Grahic Jump Location
Figure 11

Film-cooling effectiveness distributions for two blowing ratios at Main=0.45 with showerhead ejection

Grahic Jump Location
Figure 12

Film-cooling effectiveness distributions for two blowing ratios at Main=0.45 without showerhead ejection

Grahic Jump Location
Figure 13

Effect of Mach number on spanwise average film-cooling effectiveness distributions with and without showerhead ejection

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