0
Research Papers: Gas Turbines: Structures and Dynamics

Experimental Study on the Friction Contact Between a Labyrinth Seal Fin and a Honeycomb Stator

[+] Author and Article Information
Tim Pychynski

Institut für Thermische Strömungsmaschinen (ITS),
Karlsruher Institut für Technologie (KIT),
Kaiserstr. 12,
Karlsruhe 76131, Germany
e-mail: tim.pychynski@kit.edu

Corina Höfler

Institut für Thermische Strömungsmaschinen (ITS),
Karlsruher Institut für Technologie (KIT),
Kaiserstr. 12,
Karlsruhe 76131, Germany
e-mail: corina.hoefler@kit.edu

Hans-Jörg Bauer

Institut für Thermische Strömungsmaschinen (ITS),
Karlsruher Institut für Technologie (KIT),
Kaiserstr. 12,
Karlsruhe 76131, Germany
e-mail: hans-joerg.bauer@kit.edu

Contributed by the Structures and Dynamics Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received July 30, 2015; final manuscript received October 5, 2015; published online November 17, 2015. Editor: David Wisler.

J. Eng. Gas Turbines Power 138(6), 062501 (Nov 17, 2015) (9 pages) Paper No: GTP-15-1382; doi: 10.1115/1.4031791 History: Received July 30, 2015; Revised October 05, 2015

This paper presents results from an extensive experimental study on the rubbing behavior of labyrinth seal fins (SFs) and a honeycomb liner. The objective of the present work is to improve the understanding of the rub behavior of labyrinth seals by quantifying the effects and interactions of sliding speed, incursion rate, seal geometry, and SF rub position on the honeycomb liner. In order to reduce the complexity of the friction system studied, this work focuses on the contact between a single SF and a single metal foil. The metal foil is positioned in parallel to the SF to represent contact between the SF and the honeycomb double foil section. A special test rig was set up enabling the radial incursion of a metal foil into a rotating labyrinth SF at a defined incursion rate of up to 0.65 mm/s and friction velocities up to 165 m/s. Contact forces, friction temperatures, and wear were measured during or after the rub event. In total, 88 rub tests including several repetitions of each rub scenario have been conducted to obtain a solid data base. The results show that rub forces are mainly a function of the rub parameters incursion rate and friction velocity. Overall, the results demonstrate a strong interaction between contact forces, friction temperature, and wear behavior of the rub system. The presented tests confirm basic qualitative observations regarding blade rubbing provided in literature.

FIGURES IN THIS ARTICLE
<>
Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Schematic drawing of a honeycomb liner and the three extreme rub positions of a labyrinth SF

Grahic Jump Location
Fig. 2

Axial front view of the rub test rig

Grahic Jump Location
Fig. 3

Imprints of inclined SF2 and perpendicular SF3 before first rub test (in mm): (a) whole fin and (b) fin tip region

Grahic Jump Location
Fig. 4

Close-up view of the measuring equipment

Grahic Jump Location
Fig. 5

Typical incursion profile

Grahic Jump Location
Fig. 6

Test matrix for all five rub scenarios (S1–S5) with varying incursion rate and rub speed

Grahic Jump Location
Fig. 7

Typical wear profile of the metal foil after rubbing with indicated initial foil geometry (left: side view and right: front view)

Grahic Jump Location
Fig. 8

Measured resulting radial and circumferential forces over time for all five rub scenarios: (a) S1: vrub=165m/s, s˙=0.024mm/s, (b) S2: vrub=55m/s, s˙=0.024mm/s, (c) S3: vrub=110m/s, s˙=0.25mm/s, (d) S4: vrub=165m/s, s˙=0.65mm/s, (e) S5: vrub=55m/s, s˙=0.65mm/s, and (f) S3b: vrub=110m/s, s˙=0.25mm/s

Grahic Jump Location
Fig. 13

Normalized measured radial contact force over final sliding distance for all rub tests

Grahic Jump Location
Fig. 12

Abrasive wear rate over the final sliding distance for all rub tests

Grahic Jump Location
Fig. 11

Wear ratio as well as time-averaged forces and temperatures for all rub scenarios: (a) wear ratio, (b) average radial forces, (c) average tangential forces, (d) average maximum foil temperature in contact zone, (e) average maximum foil temperature 1.4 mm below contact zone, and (f) average maximum peak temperature on fin tip

Grahic Jump Location
Fig. 10

Foil temperatures extracted from the IR thermocamera images over time for all five rub scenarios both in the contact zone (0) and 1.4 mm below the contact zone (1.4): (a) S1: vrub=165m/s, s˙=0.024mm/s, (b) S2: vrub=55m/s, s˙=0.024mm/s, (c) S3: vrub=110m/s, s˙=0.25mm/s, (d) S4: vrub=165m/s, s˙=0.65mm/s, (e) S5: vrub=55m/s, s˙=0.65mm/s, and (f) S3b: vrub=110m/s, s˙=0.25mm/s

Grahic Jump Location
Fig. 9

Images from IR thermocamera showing foil steady-state temperature distribution for all five rub scenarios. The direction of rotor rotation is from right to left (temperatures in °C): (a) S1: vrub=165m/s, s˙=0.024mm/s, (b) S2: vrub=55m/s, s˙=0.024mm/s, (c) S3: vrub=110m/s, s˙=0.25mm/s, (d) S4: vrub=165m/s, s˙=0.65mm/s, (e) S5: vrub=55m/s, s˙=0.65mm/s, and (f) S3b: vrub=110m/s, s˙=0.25mm/s.

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