Numerical investigation of low-pressure turbine blade separation control

A. Gross, Hermann F Fasel

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Laminar separation on the suction side of low-pressure turbine (LPT) blades at low operating Reynolds numbers can degrade overall engine efficiency and impose limitations on the flight envelope. In wind-tunnel experiments it was shown that laminar separation can be controlled by pulsed vortex generator jets. This active-flow-control technology could be transferred to real flight hardware with more confidence if the physical mechanisms involved in the control were better understood. Here, calculations of a linear LPT cascade at a Reynolds number based on axial chord of 2.5 × 104 are presented and compared to experimental data. Good agreement was observed between numerical and experimental results, except in the separated region near the trailing edge. In two-dimensional calculations separation was controlled by pulsed blowing through a slot upstream of the flow separation location. The blade pitch was then increased by 25% to obtain a larger region of separated flow. Again, using pulsed blowing through a slot, the separation could be controlled, and an increase of 19% in the time-averaged ratio of lift and drag was achieved.

Original languageEnglish (US)
Pages (from-to)2514-2525
Number of pages12
JournalAIAA Journal
Volume43
Issue number12
DOIs
StatePublished - Dec 2005

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Turbomachine blades
Turbines
Blow molding
Reynolds number
Flight envelopes
Cascades (fluid mechanics)
Flow separation
Flow control
Wind tunnels
Drag
Vortex flow
Engines
Hardware
Experiments

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Numerical investigation of low-pressure turbine blade separation control. / Gross, A.; Fasel, Hermann F.

In: AIAA Journal, Vol. 43, No. 12, 12.2005, p. 2514-2525.

Research output: Contribution to journalArticle

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