0
TECHNICAL PAPERS

Vortex-Wake-Blade Interaction in a Shrouded Axial Turbine

[+] Author and Article Information
J. Schlienger1

Turbomachinery Laboratory,  Swiss Federal Institute of Technology, Sonneggstrasse 3, 8092 Zurich, Switzerlandjoel.schlienger@ch.abb.com

A. I. Kalfas, R. S. Abhari

Turbomachinery Laboratory,  Swiss Federal Institute of Technology, Sonneggstrasse 3, 8092 Zurich, Switzerland

1

Presently at: ABB Turbosystems, Baden, Switzerland.

J. Turbomach 127(4), 699-707 (Feb 21, 2005) (9 pages) doi:10.1115/1.1934263 History: Received August 11, 2004; Revised February 21, 2005

This paper presents time-resolved flow field measurements at the exit of the first rotor blade row of a two stage shrouded axial turbine. The observed unsteady interaction mechanism between the secondary flow vortices, the rotor wake and the adjacent blading at the exit plane of the first turbine stage is of prime interest and analyzed in detail. The results indicate that the unsteady secondary flows are primarily dominated by the rotor hub passage vortex and the shed secondary flow field from the upstream stator blade row. The analysis of the results revealed a roll-up mechanism of the rotor wake layer into the rotor indigenous passage vortex close to the hub endwall. This interesting mechanism is described in a flow schematic within this paper. In a second measurement campaign the first stator blade row is clocked by half a blade pitch relative to the second stator in order to shift the relative position of both stator indigenous secondary flow fields. The comparison of the time-resolved data for both clocking cases showed a surprising result. The steady flow profiles for both cases are nearly identical. The analysis of the probe pressure signal indicates a high level of unsteadiness that is due to the periodic occurrence of the shed first stator secondary flow field.

FIGURES IN THIS ARTICLE
<>
Copyright © 2005 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Low speed 2-stage axial turbine LISA

Grahic Jump Location
Figure 2

Probe traversing plane at the exit of the first turbine stage (area I)

Grahic Jump Location
Figure 3

Total pressure Cpt at area I and stator incidence angle Da (relative to design intention)

Grahic Jump Location
Figure 8

Space–time diagram for relative total pressure coefficient at 25% blade span (I) 0% stator–stator∕(II) 50% stator–stator

Grahic Jump Location
Figure 7

Space–time diagram for incidence angle Da at 25% rotor blade span (underturning) (I) 0% stator–stator∕(II) 50% stator–stator

Grahic Jump Location
Figure 6

Schematic of roll-up mechanism of the wake into the secondary flow vortices

Grahic Jump Location
Figure 5

Relative total pressure and secondary flow vectors at different time steps (area I)

Grahic Jump Location
Figure 4

Relative total pressure and secondary flow vectors at different time steps (area I)

Grahic Jump Location
Figure 9

Effects of stator–stator clocking on mass-averaged flow profiles (at first rotor exit)

Grahic Jump Location
Figure 12

Time-averaged turbulence level Tup of dynamic head at exit of first rotor for 0% stator clocking (baseline) and 50% stator clocking

Grahic Jump Location
Figure 11

Pitchwise mass-averaged space–time diagram for incidence angle Δα (relative to design)

Grahic Jump Location
Figure 10

Pitchwise mass-averaged space–time diagram for relative total pressure Cptr for area (I)

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