Thermal Performance of Cooled Tips in a High-Pressure Turbine Cascade

Chao Zhou, Howard Hodson, Gary Lock

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The thermal performance of the three turbine tips was investigated. The results are presented in terms of heattransfer coefficient (h), cooling effectiveness (η), net heat-flux reduction (NHFR), and heat load. The calculations were performed using a cooled flat tip, a cooled cavity tip, and a cooled suction-side squealer tip in a cascade at a tip gap of 1.6%C. The results were validated using experimental data where possible. For an uncooled flat tip, the fluid dynamics are dominated by flow separation at the pressure-side edge. A significant benefit of ejecting coolant inside this separation bubble is shown. At the coolant mass-flow ratio M c = 0:52%, both the cooled flat tip and the cooled cavity tip are well-protected by the coolant. For the cooled suction-side squealer tip, the coolant lifts off from the tip floor and leads to not only low cooling effectiveness, but also to high heat-transfer coefficients. The effects of the coolant mass-flow ratio on the thermal performance of the tip were presented. The effects of end-wall motion on the thermal performance of the blade tip are found to be small in the current study.
Original languageEnglish
Pages (from-to)900-911
JournalJournal of Propulsion and Power
Volume28
Issue number5
DOIs
Publication statusPublished - 1 Sep 2012

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Cascades (fluid mechanics)
turbines
Coolants
turbine
cascades
Turbines
suction
cavity
coolants
cooling
fluid dynamics
heat flux
heat transfer
bubble
Cooling
Flow separation
Thermal load
Fluid dynamics
mass flow
Heat transfer coefficients

Cite this

Thermal Performance of Cooled Tips in a High-Pressure Turbine Cascade. / Zhou, Chao; Hodson, Howard; Lock, Gary.

In: Journal of Propulsion and Power, Vol. 28, No. 5, 01.09.2012, p. 900-911.

Research output: Contribution to journalArticle

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