The ingress of hot gas through the rim seal of a gas turbine depends on the pressure difference between the mainstream flow in the turbine annulus and that in the wheel-space radially inward of the seal. This paper describes experimental measurements which quantify the effect of ingress on both the stator and rotor disks in a wheel-space pressurized by sealing flow. Infrared (IR) sensors were developed and calibrated to accurately measure the temperature history of the rotating disk surface during a transient experiment, leading to an adiabatic effectiveness. The performance of four generic (though engine-representative) single- and double-clearance seals was assessed in terms of the variation of adiabatic effectiveness with sealing flow rate. The measurements identify a so-called thermal buffering effect, where the boundary layer on the rotor protects the disk from the effects of ingress. It was shown that the effectiveness on the rotor was significantly higher than the equivalent stator effectiveness for all rim seals tested. Although the ingress through the rim seal is a consequence of an unsteady, three-dimensional flow field, and the cause–effect relationship between pressure and the sealing effectiveness is complex, the time-averaged experimental data are shown to be successfully predicted by relatively simple semi-empirical models, which are described in a separate paper. Of particular interest to the designer, significant ingress can enter the wheel-space before its effect is sensed by the rotor.

References

References
1.
Owen
,
J. M.
,
2011
, “
Prediction of Ingestion Through Turbine Rim Seals. Part I—Rotationally Induced Ingress
,”
ASME J. Turbomach.
,
133
(
3
), p.
031005
.
2.
Owen
,
J. M.
,
2011
, “
Prediction of Ingestion Through Turbine Rim Seals. Part II—Externally Induced and Combined Ingress
,”
ASME J. Turbomach.
,
133
(
3
), p.
031006
.
3.
Wang
,
C. Z.
,
Mathiyalagan
,
S. P.
,
Johnson
,
B. V.
,
Glahn
,
J. A.
, and
Cloud
,
D. F.
,
2012
, “
Rim Seal Ingestion in a Turbine Stage From 360-Degree Time-Dependent Numerical Simulations
,”
ASME J. Turbomach.
,
136
(
3
), p.
031007
.
4.
Bohn
,
D. E.
, and
Wolff
,
M.
,
2003
, “
Improved Formulation to Determine Minimum Sealing Flow—Cw, min—for Different Sealing Configurations
,”
ASME
Paper No. GT2003-38465.
5.
Zhou
,
D. W.
,
Roy
,
R. P.
,
Wang
,
C. Z.
, and
Glahn
,
J. A.
,
2011
, “
Main Gas Ingestion in a Turbine Stage for Three Rim Cavity Configurations
,”
ASME J. Turbomach.
,
133
(
3
), p.
031023
.
6.
Sangan
,
C. M.
,
Pountney
,
O. J.
,
Zhou
,
K.
,
Wilson
,
M.
,
Owen
,
J. M.
, and
Lock
,
G. D.
,
2013
, “
Experimental Measurements of Ingestion Through Turbine Rim Seals. Part I—Externally-Induced Ingress
,”
ASME J. Turbomach.
,
135
(
2
), p.
021012
.
7.
Eastwood
,
D.
,
Coren
,
D. D.
,
Long
,
C. A.
,
Atkins
,
N. R.
,
Childs
,
P. R. N.
,
Scanlon
,
T. J.
, and
Guijarro-Valencia
,
A.
,
2012
, “
Experimental Investigation of Turbine Stator Well Rim Seal, Re-Ingestion and Interstage Seal Flows Using Gas Concentration Techniques and Displacement Measurements
,”
ASME J. Eng. Gas Turbines Power
,
134
(
8
), p.
082501
.
8.
Palafox
,
P.
,
Ding
,
Z.
,
Bailey
,
J. M.
,
Vanduser
,
T.
,
Kirtley
,
K.
,
Moore
,
K.
, and
Chupp
,
R.
,
2013
, “
A New 1.5 Turbine Wheelspace Hot Gas Ingestion Rig (HGIR)—Part I: Experimental Test Vehicle, Measurement Capability and Baseline Results
,”
ASME
Paper No. GT2013-96020.
9.
Barringer
,
M.
,
Coward
,
A.
,
Clark
,
K.
,
Thole
,
K. A.
,
Schmitz
,
J.
,
Wagner
,
J.
,
Alvin
,
M. A.
,
Burke
,
P.
, and
Dennis
,
R.
,
2014
, “
The Design of a Steady Aero Thermal Research Turbine (START) for Studying Secondary Flow Leakages and Airfoil Heat Transfer
,”
ASME
Paper No. GT2014-25570.
10.
Sangan
,
C. M.
,
Pountney
,
O. J.
,
Scobie
,
J. A.
,
Wilson
,
M.
,
Owen
,
J. M.
, and
Lock
,
G. D.
,
2013
, “
Experimental Measurements of Ingestion Through Turbine Rim Seals. Part 3—Single and Double Seals
,”
ASME J. Turbomach.
,
135
(
5
), p.
051011
.
11.
Dadkhah
,
S.
,
Turner
,
A. B.
, and
Chew
,
J. W.
,
1992
, “
Performance of Radial Clearance Rim Seals in Upstream and Downstream Rotor–Stator Wheelspaces
,”
ASME J. Turbomach.
,
114
(
2
), pp.
439
445
.
12.
Pountney
,
O. J.
,
Sangan
,
C. M.
,
Lock
,
G. D.
, and
Owen
,
J. M.
,
2013
, “
Effect of Ingestion on Temperature of Turbine Discs
,”
ASME J. Turbomach.
,
135
(
5
), p.
051010
.
13.
Mear
,
L. I.
,
Owen
,
J. M.
, and
Lock
,
G. D.
,
2015
, “
Theoretical Model to Determine Effect of Ingress on Turbine Discs
,”
ASME
Paper No. GT2015-42326.
14.
Owen
,
J. M.
, and
Rogers
,
R. H.
,
1989
,
Flow and Heat Transfer in Rotating-Disc Systems—Rotor–Stator Systems
, Vol.
1
,
Research Studies Press
,
Taunton, UK
.
15.
Coren
,
D.
,
Childs
,
P. R. N.
, and
Long
,
C. A.
,
2009
, “
Windage Sources in Smooth-Walled Rotating Disc Systems
,”
Proc. Inst. Mech. Eng. Part C
,
223
(
4
), pp.
873
888
.
16.
Long
,
C. A.
,
Miles
,
A. L.
, and
Coren
,
D. D.
,
2012
, “
Windage Measurements in a Rotor–Stator Cavity With Rotor Mounted Protrusions and Bolts
,”
ASME
Paper No. GT2012-69385.
17.
Barry
,
T.
,
Fuller
,
G.
,
Hayatleh
,
K.
, and
Lidgey
,
J.
,
2011
, “
Self-Calibrating Infrared Thermometer for Low-Temperature Measurement
,”
IEEE Instrum. Meas.
,
60
(
6
), pp.
2047
2052
.
18.
Childs
,
P. R. N.
,
2001
.,
Practical Temperature Measurement
,
Butterworth-Heinemann
,
Oxford, UK
.
19.
Cho
,
G.
,
2014
, “
Hot Gas Ingress Through Turbine Rim Seals: Heat Transfer and Fluid Dynamics
,” Ph.D. thesis, University of Bath, Bath, UK.
20.
Ireland
,
P. T.
,
Gillespie
,
D. R. H.
, and
Wang
,
Z.
,
1996
, “
Heater Element
,” European Patent No. 0847679 B1.
21.
Kakade
,
V. U.
,
Lock
,
G. D.
,
Wilson
,
M.
,
Owen
,
J. M.
, and
Mayhew
,
J. E.
,
2009
, “
Accurate Heat Transfer Measurements Using Thermochromic Liquid Crystal. Part 1—Calibration and Characteristics of Crystals
,”
Int. J. Heat Fluid Flow
,
30
(
5
), pp.
939
949
.
22.
Holman
,
J. P.
,
2010
,
Heat Transfer
, 10th ed.,
McGraw-Hill
,
Boston, MA
.
23.
White
,
F. M.
,
1994
,
Fluid Mechanics
, 3rd ed.,
McGraw-Hill
, New York.
24.
Kakade
,
V. U.
,
Lock
,
G. D.
,
Wilson
,
M.
,
Owen
,
J. M.
, and
Mayhew
,
J. E.
,
2009
, “
Accurate Heat Transfer Measurements Using Thermochromic Liquid Crystal. Part 2—Application to a Rotating Disc
,”
Int. J. Heat Fluid Flow
,
30
(
5
), pp.
950
959
.
25.
Sangan
,
C. M.
,
Pountney
,
O. J.
,
Zhou
,
K.
,
Wilson
,
M.
,
Owen
,
J. M.
, and
Lock
,
G. D.
,
2013
, “
Experimental Measurements of Ingestion Through Turbine Rim Seals. Part II—Rotationally-Induced Ingress
,”
ASME J. Turbomach.
,
135
(
2
), p.
021013
.
You do not currently have access to this content.