Research Papers: Forced Convection

Film Cooling of Cylindrical Hole With a Downstream Short Crescent-Shaped Block

[+] Author and Article Information
Baitao An

e-mail: anbt@mail.etp.ac.cn

Sijing Zhou

Institute of Engineering Thermophysics,
Chinese Academy of Sciences,
Beijing 100190, China

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received December 12, 2011; final manuscript received September 6, 2012; published online February 8, 2013. Assoc. Editor: Frank Cunha.

J. Heat Transfer 135(3), 031702 (Feb 08, 2013) (9 pages) Paper No: HT-11-1560; doi: 10.1115/1.4007879 History: Received December 12, 2011; Revised September 06, 2012

This paper presents a method to improve the film-cooling effectiveness of cylindrical holes. A short crescent-shaped block is placed at the downstream of a cylindrical cooling hole. The block shape is defined by a number of geometric parameters including block height, length and width, etc. The single row hole on a flat plate with inclination angle of 30 deg, pitch ratio of 3, and length-diameter ratio of 6.25 was chosen as the baseline test case. Film-cooling effectiveness for the cylindrical hole with or without the downstream short crescent-shaped block was measured by using the pressure sensitive paint (PSP) technique. The density ratio of coolant (argon) to mainstream air is 1.38. The blowing ratios vary from 0.5 to 1.25. The results showed that the lateral averaged cooling effectiveness is increased remarkably when the downstream block is present. The downstream short block allows the main body of the coolant jet to pass over the block top and to form a new down-wash vortex pair, which increases the coolant spread in the lateral direction. The effects of each geometrical parameter of the block on the film-cooling effectiveness were studied in detail.

Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Fig. 1

Schematic of the test facilities

Grahic Jump Location
Fig. 2

PSP calibration curves

Grahic Jump Location
Fig. 3

Geometry of downstream short crescent-shaped block: (a) top view and (b) side view

Grahic Jump Location
Fig. 4

Schematic of tested flat plate with film-cooling holes

Grahic Jump Location
Fig. 5

Top views of different block geometries: (a) with/without the block, (b) W variation, (c) δ variation, (d) B variation, (e) H variation, and (f) λ variation

Grahic Jump Location
Fig. 6

Comparison of adiabatic effectiveness of cylindrical hole with published data: (a) centerline cooling effectiveness and (b) lateral averaged cooling effectiveness

Grahic Jump Location
Fig. 7

Local distributions of adiabatic film-cooling effectiveness: (a) ORI case and (b) BSL case

Grahic Jump Location
Fig. 8

Comparison of centerline cooling effectiveness under different blowing ratios

Grahic Jump Location
Fig. 9

Comparison of lateral cooling effectiveness distributions: (a) x/D = 5 and (b) x/D = 10

Grahic Jump Location
Fig. 10

Illustration of cylindrical hole jet with downstream crescent-shaped block

Grahic Jump Location
Fig. 11

Comparison of lateral averaged effectiveness distributions under different blowing ratios

Grahic Jump Location
Fig. 12

Schematic of coolant flow at the centerline: (a) without the block and (b) with the block

Grahic Jump Location
Fig. 13

Comparison of area averaged cooling effectiveness under different blowing ratios

Grahic Jump Location
Fig. 14

Lateral averaged effectiveness distributions for varied block W/D

Grahic Jump Location
Fig. 15

Lateral averaged effectiveness distributions for varied block δ/B

Grahic Jump Location
Fig. 16

Lateral averaged effectiveness distributions for varied block B/D

Grahic Jump Location
Fig. 17

Lateral averaged effectiveness distributions for varied block H/D

Grahic Jump Location
Fig. 18

Lateral averaged effectiveness distributions for varied block λ/D




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