0
Research Papers

The Effect of Airfoil Clocking on Efficiency and Noise of Low Pressure Turbines

[+] Author and Article Information
Raúl Vázquez

ITP, Industria de Turbo Propulsores S.A.,
UPM, Universidad Politécnica,
Madrid, Spain
e-mail: raul.vazquez@itp.es

Diego Torre

ITP, Industria de Turbo Propulsores S.A.,
UPM, Universidad Politécnica,
Madrid, Spain
e-mail: diego.torre@itp.es

Adolfo Serrano

ITP Industria de Turbo Propulsores S.A.,
Madrid, Spain
e-mail: adolfo.serrano@itp.es

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received June 21, 2013; final manuscript received August 9, 2013; published online November 15, 2013. Editor: Ronald Bunker.

J. Turbomach 136(6), 061006 (Nov 15, 2013) (9 pages) Paper No: TURBO-13-1106; doi: 10.1115/1.4025572 History: Received June 21, 2013; Revised August 09, 2013

The effect of airfoil clocking (stator-stator interaction) on efficiency and noise of low pressure turbines (LPT) was investigated experimentally in a multistage turbine high-speed rig. The rig consisted of three stages of a state-of-the-art LPT. The stages were characterized by a very high wall-slope angle, reverse cut-off design, very high lift, and very high aspect ratio airfoils. The rig had identical blade count for the second and third stators. The circumferential position of the second stator was individually adjusted with respect to the third stator. Eight different circumferential clocking locations over one pitch were back-to-back tested. The rig was heavily instrumented with miniature five hole probes, hot wires, hot films, total pressure and temperature rakes, pressure tappings on the airfoil surface, two array of Kulites in a rotatory module, etc. Every clocking location was tested with the same instrumentation and at the same operating conditions with the intention of determining the impact of the clocking on the overall efficiency and noise. Due to the large amount of data, the results of this test will be reported in several papers. The present paper contains the impact on the overall efficiency, radial traverses, static pressure fields on the airfoils and averaged sound pressure levels in the duct. The comparison of the results suggests that the efficiency is weakly affected by clocking; however the effect on noise is noticeable for some acoustic tones at certain operating conditions.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 2

Measured and calculated Cp distributions for midspan of the third stator at design conditions

Grahic Jump Location
Fig. 3

Measured variation of efficiency at hub region with stator 2 clocking position

Grahic Jump Location
Fig. 4

Measured variation of efficiency at midspan region with stator 2 clocking position

Grahic Jump Location
Fig. 5

Measured variation of efficiency at tip region with stator 2 clocking position

Grahic Jump Location
Fig. 6

Measured variation of global efficiency with stator 2 clocking position

Grahic Jump Location
Fig. 7

Measured nondimensional total pressure loss contours at hub region for clp1 (a) and clp5 (b)

Grahic Jump Location
Fig. 8

Measured non dimensional total pressure loss contours at tip region for clp1 (a) and clp6 (b)

Grahic Jump Location
Fig. 9

Effect of ngv2 clocking position on measured exit swirl angle

Grahic Jump Location
Fig. 10

Measured Cp distributions for midspan of the third stator at design conditions for clocking positions 1, 3, 5, and 7

Grahic Jump Location
Fig. 11

Variation of efficiency at midspan with stator 2 clocking position for different Reynolds numbers

Grahic Jump Location
Fig. 12

Variation of rig efficiency with Reynolds number for several stator 2 clocking positions

Grahic Jump Location
Fig. 13

Averaged sound spectrum for 100% nominal speed

Grahic Jump Location
Fig. 14

Stability (top) and repeatability (bottom)

Grahic Jump Location
Fig. 15

Clocking sensitivity at 85% (top) and 120% (bottom) of nominal (ADP) shaft speed

Grahic Jump Location
Fig. 16

Two sources model versus measurements

Grahic Jump Location
Fig. 17

Analytical estimation based on the two source model

Tables

Errata

Discussions

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