0
Research Papers

Effect of Density Ratio on Film-Cooling Effectiveness Distribution and Its Uniformity for Several Hole Geometries on a Flat Plate

[+] Author and Article Information
Jiaxu Yao, Jin Xu, Ke Zhang

State Key Laboratory for Strength and Vibration
of Mechanical Structures,
Xi'an Jiaotong University,
Xi'an, Shaanxi 710049, China

Jiang Lei

State Key Laboratory for Strength and Vibration
of Mechanical Structures,
Xi'an Jiaotong University,
Xi'an, Shaanxi 710049, China
e-mail: leijiang@mail.xjtu.edu.cn

Lesley M. Wright

Department of Mechanical Engineering,
Baylor University,
Waco, TX 76798-7356
e-mail: lesley_wright@tamu.edu

1Corresponding author.

2Present address: Turbine Heat Transfer Laboratory, Department of Mechanical Engineering, Texas A&M University, College Station, TX 77843-3123.

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received May 31, 2018; final manuscript received October 18, 2018; published online January 22, 2019. Editor: Kenneth Hall.

J. Turbomach 141(5), 051008 (Jan 22, 2019) (10 pages) Paper No: TURBO-18-1119; doi: 10.1115/1.4041810 History: Received May 31, 2018; Revised October 18, 2018

The film cooling effectiveness distribution and its uniformity downstream of a row of film cooling holes on a flat plate are investigated by pressure sensitive paint (PSP) under different density ratios. Several hole geometries are studied, including streamwise cylindrical holes, compound-angled cylindrical holes, streamwise fan-shape holes, compound-angled fan-shape holes, and double-jet film-cooling (DJFC) holes. All of them have an inclination angle (θ) of 35 deg. The compound angle (β) is 45 deg. The fan-shape holes have a 10 deg expansion in the spanwise direction. For a fair comparison, the pitch is kept as 4d for the cylindrical and the fan-shape holes, and 8d for the DJFC holes. The uniformity of effectiveness distribution is described by a new parameter (Lateral-Uniformity, LU) defined in this paper. The effects of density ratios (DR = 1.0, 1.5 and 2.5) on the film-cooling effectiveness and its uniformity are focused. Differences among geometries and effects of blowing ratios (M = 0.5, 1.0, 1.5, and 2.0) are also considered. The results show that at higher density ratios, the lateral spread of the discrete-hole geometries (i.e., the cylindrical and the fan-shape holes) is enhanced, while the DJFC holes is more advantageous in film-cooling effectiveness. Mostly, a higher lateral-uniformity is obtained at DR = 2.5 due to better coolant coverage and enhanced lateral spread, but the effects of the density ratio on the lateral-uniformity are not monotonic in some cases. Utilizing the compound angle configuration leads to an increased lateral-uniformity due to a stronger spanwise motion of the jet. Generally, with a higher blowing ratio, the lateral-uniformity of the discrete-hole geometries decreases due to narrower traces, while that of the DJFC holes increases due to a stronger spanwise movement.

FIGURES IN THIS ARTICLE
<>
Copyright © 2019 by ASME
Your Session has timed out. Please sign back in to continue.

References

Han, J. C. , Dutta, S. , and Ekkad, S. , 2012, Gas Turbine Heat Transfer and Cooling Technology, CRC Press, New York.
Bogard, D. G. , and Thole, K. A. , 2006, “Gas Turbine Film Cooling,” AIAA J. Propul. Power, 22(2), pp. 249–270. [CrossRef]
Sinha, A. K. , Bogard, D. G. , and Crawford, M. E. , 1991, “Film-Cooling Effectiveness Downstream of a Single Row of Holes With Variable Density Ratio,” ASME J. Turbomach., 113(3), pp. 442–449. [CrossRef]
Walters, D. K. , and Leylek, J. H. , 2000, “A Detailed Analysis of Film-Cooling Physics—Part I: Streamwise Injection With Cylindrical Holes,” ASME J. Turbomach., 122(1), pp. 102–112. [CrossRef]
McGovern, K. T. , and Leylek, J. H. , 2000, “A Detailed Analysis of Film Cooling Physics—Part II: Compound-Angle Injection With Cylindrical Holes,” ASME J. Turbomach., 122(1), pp. 113–121. [CrossRef]
Chen, A. F. , Li, S. J. , and Han, J. C. , 2014, “Film Cooling With Forward and Backward Injection for Cylindrical and Fan-Shaped Holes Using PSP Measurement Technique,” ASME Paper No. GT2014-26232.
Hyams, D. G. , and Leylek, J. H. , 2000, “A Detailed Analysis of Film Cooling Physics—Part III: Streamwise Injection With Shaped Holes,” ASME J. Turbomach., 122(1), pp. 122–132. [CrossRef]
Wright, L. M. , McClain, S. T. , Brown, C. P. , and Harmon, W. V. , “Assessment of a Double Hole Film Cooling Geometry Using S-PIV and PSP,” ASME Paper No. GT2013-94614.
Bunker, R. S. , “Film Cooling Effectiveness Due to Discrete Holes Within a Transverse Surface Slot,” ASME Paper No. GT2002-30178.
Fric, T. F. , and Campbell, R. P. , 2002, “Method for Improving the Cooling Effectiveness of a Gaseous Coolant Stream Which Flows Through a Substrate, and Related Articles of Manufacture,” U.S. Patent No. 6,383,602. https://patents.google.com/patent/US6383602B1/en
Kusterer, K. , Tekin, N. , Reiners, F. , Bohn, D. , Sugimoto, T. , Tanaka, R. , and Kazari, M. , 2013, “Highest-Efficient Film Cooling by Improved Nekomimi Film Cooling Holes—Part 1: Ambient Air Flow Conditions,” ASME Paper No. GT2013-95027.
Kusterer, K. , Tekin, N. , Kasiri, A. , Bohn, D. , Sugimoto, T. , Tanaka, R. , and Kazari, M. , 2013, “Highest-Efficient Film Cooling by Improved Nekomimi Film Cooling Holes—Part 2: Hot Gas Flow Conditions,” ASME Paper No. GT2013-95042.
Heidmann, J. D. , and Ekkad, S. , 2008, “A Novel Antivortex Turbine Film-Cooling Hole Concept,” ASME J. Turbomach., 130(3), p. 031020. [CrossRef]
Kusterer, K. , Bohn, D. , Sugimoto, T. , and Tanaka, R. , 2007, “Double-Jet Ejection of Cooling Air for Improved Film Cooling,” ASME J. Turbomach., 129(4), pp. 809–815. [CrossRef]
Ekkad, S. , and Han, J. C. , 2013, “A Review of Hole Geometry and Coolant Density Effect on Film Cooling,” ASME Paper No. HT2013-17250.
Wright, L. M. , McClain, S. T. , and Clemenson, M. D. , 2011, “Effect of Density Ratio on Flat Plate Film Cooling With Shaped Holes Using PSP,” ASME J. Turbomach., 133(4), p. 041011. [CrossRef]
Vinton, K. R. , Watson, T. B. , Wright, L. M. , Crites, D. C. , Morris, M. C. , and Riahi, A. , 2016, “Combined Effects of Freestream Pressure Gradient and Density Ratio on the Film Cooling Effectiveness of round and Shaped Holes on a Flat Plate,” ASME Paper No. GT2016-56175.
Watson, T. B. , Nahang-Toudeshki, S. , Wright, L. M. , Crites, D. C. , Morris, M. C. , and Riahi, A. , 2016, “Application of S-PIV for Investigation of round and Shaped Film Cooling Holes at High Density Ratios,” ASME Paper No. GT2016-56209.
Javadi, K. , and Javadi, A. , 2008, “Introducing Film Cooling Uniformity Coefficient (CUC),” ASME Paper No. IMECE2008-68502.
Yao, J. , Xu, J. , Zhang, K. , Lei, J. , and Wright, L. M. , 2017, “Interaction of Flow and Film-Cooling Effectiveness Between Double-Jet Film-Cooling Holes With Various Spanwise Distances,” ASME Paper No. GT2017-63740.
Han, J. C. , and Rallabandi, A. , 2010, “Turbine Blade Film Cooling Using PSP Technique,” Front. Heat Mass Transfer, 1(1), pp. 1–16. [CrossRef]
Kendall, A. , and Koochesfahani, M. , 2008, “A Method for Estimating Wall Friction in Turbulent Wall-Bounded Flows,” Exp. Fluids, 44(5), pp. 773–780. [CrossRef]
Wright, L. M. , McClain, S. T. , and Clemenson, M. D. , 2011, “Effect of Freestream Turbulence Intensity on Film Cooling Jet Structure and Surface Effectiveness Using PIV and PSP,” ASME J. Turbomach., 133(4), p. 041023. [CrossRef]
Eberly, M. K. , and Thole, K. A. , 2014, “Time-Resolved Film-Cooling Flows at High and Low Density Ratios,” ASME J. Turbomach., 136(6), p. 061003. [CrossRef]
Kline, S. J. , and McClintock, F. , 1953, “Describing Uncertainties in Single-Sample Experiments,” Mech. Eng., 75(1), pp. 3–8.

Figures

Grahic Jump Location
Fig. 5

Mainstream boundary layer velocity profile

Grahic Jump Location
Fig. 4

Pressure sensitive paint calibration curve

Grahic Jump Location
Fig. 3

Schematic of (a) cylindrical holes, (b) fan-shape holes, and (c) DJFC holes

Grahic Jump Location
Fig. 2

Test section view, showing the position of the camera and the light emitting diode lamp

Grahic Jump Location
Fig. 1

Schematic of the experiment setup (the plenum has two entrances at opposing sides, but only one can be seen here)

Grahic Jump Location
Fig. 6

Film-cooling effectiveness for streamwise cylindrical holes comparing with open literature (a) DR = 1.0, centerline, (b) DR = 1.0, laterally averaged, and (c) DR = 1.5, centerline

Grahic Jump Location
Fig. 7

(a) Film-cooling effectiveness distribution, (b) laterally averaged Film-cooling effectiveness, and (c) lateral-uniformity at M = 0.5

Grahic Jump Location
Fig. 8

(a) Film-cooling effectiveness distribution, (b) laterally averaged film-cooling effectiveness, and (c) Lateral-uniformity at M = 1.0

Grahic Jump Location
Fig. 9

(a) Film-cooling effectiveness distribution, (b) laterally averaged film-cooling effectiveness, and (c) lateral-uniformity at M = 1.5

Grahic Jump Location
Fig. 10

(a) Film-cooling effectiveness distribution, (b) laterally averaged film-cooling effectiveness, and (c) lateral-uniformity at M = 2.0

Grahic Jump Location
Fig. 11

Laterally averaged film-cooling effectiveness for different geometry

Grahic Jump Location
Fig. 12

Film-cooling effectiveness lateral-uniformity for different geometry

Tables

Errata

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