Combined effects of unsteady wake and free-stream turbulence on turbine blade film cooling with laid-back fan-shaped holes using PSP technique

Da wei Chen, Hui ren Zhu, Cun liang Liu, Hua tai Li, Bing ran Li, Dao en Zhou

Research output: Contribution to journalArticlepeer-review

56 Scopus citations

Abstract

Detailed film cooling effectiveness distribution for a gas turbine blade under the effects of unsteady wakes and oncoming free-stream turbulence intensities was obtained using pressure sensitive paint (PSP) technique. Tests were performed on a linear cascade at Reynolds number of 3.85 × 105 based on the blade chord at cascade exit. Upstream unsteady wakes were simulated using a spoke-wheel type wake generator. The test blade has three rows of compound angled cylindrical film holes at the leading edge, five rows of laid-back fan-shaped holes on the pressure surface and three rows of laid-back fan-shaped holes on the suction surface. The wake Strouhal number was varied from 0 to 0.36 and three mass flux ratios were determined. The oncoming free-stream turbulence intensities are 2.7% and 26.9%, respectively. Results show that the effect of the mass flux ratio on the film cooling effectiveness decreases under the high turbulence intensity and unsteady wake conditions. In most regions of the blade surface, the film cooling effectiveness decreases with the increase of wake Strouhal number, and the free-stream turbulence superimposed on the unsteady wake reduces the film cooling effectiveness further. The effect of the unsteady wake decreases under the high free-stream turbulence conditions.

Original languageEnglish
Pages (from-to)382-392
Number of pages11
JournalInternational Journal of Heat and Mass Transfer
Volume133
DOIs
StatePublished - Apr 2019

Keywords

  • Film cooling effectiveness
  • Laid-back fan-shaped hole
  • Mass flux ratio
  • PSP
  • Strouhal number
  • Turbine blade
  • Turbulence intensity
  • Wake

Fingerprint

Dive into the research topics of 'Combined effects of unsteady wake and free-stream turbulence on turbine blade film cooling with laid-back fan-shaped holes using PSP technique'. Together they form a unique fingerprint.

Cite this