0
Research Papers

Separated Flow Measurements on a Highly Loaded Low-Pressure Turbine Airfoil

[+] Author and Article Information
Ralph J. Volino

Department of Mechanical Engineering, United States Naval Academy, Annapolis, MD 21402volino@usna.edu

J. Turbomach 132(1), 011007 (Sep 16, 2009) (10 pages) doi:10.1115/1.3104608 History: Received July 07, 2008; Revised February 02, 2009; Published September 16, 2009

Boundary layer separation, transition, and reattachment have been studied on a new, very high lift, low-pressure turbine airfoil. Experiments were done under low freestream turbulence conditions on a linear cascade in a low speed wind tunnel. Pressure surveys on the airfoil surface and downstream total pressure loss surveys were documented. Velocity profiles were acquired in the suction side boundary layer at several streamwise locations using hot-wire anemometry. Cases were considered at Reynolds numbers (based on the suction surface length and the nominal exit velocity from the cascade) ranging from 25,000 to 330,000. In all cases, the boundary layer separated, but at high Reynolds number the separation bubble remained very thin and quickly reattached after transition to turbulence. In the low Reynolds number cases, the boundary layer separated and did not reattach, even when transition occurred. This behavior contrasts with previous research on other airfoils, in which transition, if it occurred, always induced reattachment, regardless of Reynolds number.

Copyright © 2010 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Comparison of inviscid pressure profiles for the Pack B, L1M, and L1A airfoils: (a) Cp versus axial position; (b) Cp versus streamwise location

Grahic Jump Location
Figure 2

Acceleration, K Re, versus streamwise location for Pack B, L1M, and L1A airfoils based on inviscid solution

Grahic Jump Location
Figure 3

Schematic of linear cascade

Grahic Jump Location
Figure 5

Lift based on integrated Cp profile

Grahic Jump Location
Figure 6

Total pressure loss coefficient at 0.63Cx downstream of cascade

Grahic Jump Location
Figure 7

Integrated total pressure loss coefficient for center blade as function of Re

Grahic Jump Location
Figure 8

rms fluctuating streamwise velocity at 0.63Cx downstream of cascade

Grahic Jump Location
Figure 9

Profiles for Re=25,000 case: (a) mean velocity, (b) u′/Ue, and (c) intermittency

Grahic Jump Location
Figure 10

Turbulence spectra for Re=25,000 case

Grahic Jump Location
Figure 11

Profiles for Re=50,000 case: (a) mean velocity, (b) u′/Ue, and (c) intermittency

Grahic Jump Location
Figure 12

Turbulence spectra for Re=50,000 case

Grahic Jump Location
Figure 13

Profiles for Re=100,000 case: (a) mean velocity, (b) u′/Ue, and (c) intermittency

Grahic Jump Location
Figure 14

Turbulence spectra for Re=100,000 case

Grahic Jump Location
Figure 15

Profiles for Re=200,000 case: (a) mean velocity, (b) u′/Ue, and (c) intermittency

Grahic Jump Location
Figure 16

Turbulence spectra for Re=200,000 case

Grahic Jump Location
Figure 17

Profiles for Re=300,000 case: (a) mean velocity, (b) u′/Ue, and (c) intermittency

Grahic Jump Location
Figure 18

Turbulence spectra for Re=300,000 case

Grahic Jump Location
Figure 19

Shape factor for high Re cases

Grahic Jump Location
Figure 20

Skin friction coefficient for high Re cases

Grahic Jump Location
Figure 21

Frequencies of spectral peaks along with predicted most unstable TS frequencies at separation location

Grahic Jump Location
Figure 22

Predicted and experimental transition start location: error bars indicate uncertainty due to finite spacing of measurement stations

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