Jet impingement cooling has been extensively used in the leading edge region of a gas turbine blade. This study focuses on the effect of jet impinging position on leading edge heat transfer. The test model is composed of a semicylindrical target plate, side exit slots, and an impingement jet plate. A row of cylindrical injection holes is located along the axis (normal jet) or the edge (tangential jet) of the semicylinder, on the jet plate. The jet-to-target-plate distance to jet diameter ratio (z/d) is 5 and the ratio of jet-to-jet spacing to jet diameter (s/d) is 4. The jet Reynolds number is varied from 10,000 to 30,000. Detailed impingement heat transfer coefficient distributions were experimentally measured by using the transient liquid crystal (TLC) technique. To understand the thermal flow physics, numerical simulations were performed using Reynolds-averaged Navier–Stokes (RANS) with two turbulence models: realizable k–ε (RKE) and shear stress transport k–ω model (SST). Comparisons between the experimental and the numerical results are presented. The results indicate that the local Nusselt numbers on the test surface increase with the increasing jet Reynolds number. The tangential jets provide more uniform heat transfer distributions as compared with the normal jets. For the normal jet impingement and the tangential jet impingement, the RKE model provides better prediction than the SST model. The results can be useful for selecting a jet impinging position in order to provide the proper cooling distribution inside a turbine blade leading edge region.

References

References
1.
Boyce
,
M. P.
,
2002
,
Gas Turbine Engineering Handbook
, Butterworth-Heinemann, Oxford, UK.
2.
Han
,
J. C.
,
Dutta
,
S.
, and
Ekkad
,
S.
,
2000
,
Gas Turbine Heat Transfer and Cooling Technology
,
Taylor and Francis
,
New York
.
3.
Amano
,
R. S.
, and
Sundén
,
B.
,
2014
,
Impingement Jet Cooling in Gas Turbines
,
WIT Press, Southampton, UK
.
4.
Weigand
,
B.
, and
Spring
,
S.
,
2011
, “
Multiple Jet Impingement—A Review
,”
Heat Transfer Res.
,
42
(
2
), pp.
101
142
.
5.
Wright
,
L. M.
, and
Han
,
J. C.
,
2013
, “Heat Transfer Enhancement for Turbine Blade Internal Cooling,”
ASME
Paper No. HT2013-17813.
6.
Chupp
,
R. E.
,
Helms
,
D. E.
,
McFadden
,
P. W.
, and
Brown
,
T. R.
,
1969
, “
Evaluation of Internal Heat Transfer Coefficients for Impingement Cooled Turbine Airfoils
,”
AIAA J. Aircr.
,
6
(
3
), pp.
203
208
.
7.
Florschuetz
,
L. W.
, and
Isoda
,
Y.
,
1982
, “
Flow Distributions and Discharge Coefficient Effects for Jet Array Impingement With Initial Crossflow
,”
ASME J. Eng. Power
,
105
(2), pp. 296–304.
8.
Florschuetz
,
L. W.
,
Truman
,
C. R.
, and
Metzger
,
D. E.
,
1981
, “
Streamwise Flow and Heat Transfer Distributions for Jet Array Impingement With Crossflow
,”
ASME J. Heat Transfer
,
103
(2), pp.
337
342
.
9.
Florschuetz
,
L. W.
,
Berry
,
R. A.
, and
Mezger
,
D. E.
,
1980
, “
Periodic Streamwise Variations of Heat Transfer Coefficients for Inline and Staggered Arrays of Circular Jets With Crossflow of Spent Air
,”
ASME J. Heat Transfer
,
102
(1), pp.
132
137
.
10.
Huang
,
Y.
,
Ekkad
,
S. V.
, and
Han
,
J. C.
,
1998
, “
Detailed Heat Transfer Distributions Under an Array of Orthogonal Impinging Jets
,”
AIAA J. Thermophys. Heat Transfer
,
12
(1), pp. 73–79.
11.
Ekkad
,
S. V.
,
Huang
,
Y.
, and
Han
,
J. C.
,
1999
, “
Impingement Heat Transfer on Target Plate With Film Cooling Holes
,”
AIAA J. Thermophys. Heat Transfer
,
13
(
4
), pp.
522
528
.
12.
Jordan
,
C. N.
,
Wright
,
L. M.
, and
Crites
,
D. C.
,
2012
, “Impingement Heat Transfer on a Cylindrical, Concave Surface With Varying Jet Geometries,”
ASME
Paper No. GT2012-68818.
13.
Jordan
,
C. N.
,
Wright
,
L. M.
, and
Crites
,
D. C.
,
2012
, “Effect of Impingement Supply Condition on Leading Edge Heat Transfer With Rounded Impinging Jets,”
ASME
Paper No. HT2012-58410.
14.
Jordan
,
C. N.
,
Elston
,
C. A.
,
Wright
,
L. M.
, and
Crites
,
D. C.
,
2013
, “Leading Edge Impingement With Racetrack-Shaped Jets and Varying Inlet Supply Conditions,”
ASME
Paper No. GT2013-94611.
15.
Azad
,
G. M.
,
Huang
,
Y.
, and
Han
,
J. C.
,
2000
, “
Jet Impingement Heat Transfer on Pinned Surfaces Using a Transient Liquid Crystal Technique
,”
Eighth International Symposium on Transport Phenomena and Dynamics of Rotating Machinery
(
ISROMAC
), Honolulu, HI, Mar. 26–30, pp.
731
738
.
16.
Azad
,
G. M.
,
Huang
,
Y.
, and
Han
,
J. C.
,
2000
, “
Jet Impingement Heat Transfer on Dimpled Surfaces Using a Transient Liquid Crystal Technique
,”
AIAA J. Thermophys. Heat Transfer
,
14
(
2
), pp.
186
193
.
17.
Mhetras
,
S.
,
Han
,
J.-C.
, and
Huh
,
M.
,
2014
, “
Impingement Heat Transfer From Jet Arrays on Turbulent Target Walls at Large Reynolds Numbers
,”
ASME Trans. J. Therm. Sci. Eng. Appl.
,
6
(
2
), p.
021003
.
18.
Buzzard
,
W.
,
Ren
,
Z.
,
Ligrani
,
P.
,
Nakamata
,
C.
, and
Ueguchi
,
S.
,
2016
, “Influences of Target Surface Roughness on Impingement Jet Array Heat Transfer—Part 1: Effects of Roughness Pattern, Roughness Height, and Reynolds Number,”
ASME
Paper No. GT2016-56354.
19.
Buzzard
,
W.
,
Ren
,
Z.
,
Ligrani
,
P. M.
,
Nakamata
,
C.
, and
Ueguchi
,
S.
,
2016
, “Influences of Target Surface Roughness on Impingement Jet Array Heat Transfer—Part 2: Effects of Roughness Shape, and Reynolds Number,”
ASME
Paper No. GT2016-56355.
20.
Kumar
,
B. V. N. R.
, and
Prasad
,
B. V. S. S. S.
,
2000
, “Computational Investigation of Flow and Heat Transfer for a Row of Circular Jets Impinging on a Concave Surface,”
ASME
Paper No. GT2006-90851.
21.
Kumar
,
B. V. N. R.
, and
Prasad
,
B. V. S. S. S. P.
,
2008
, “
Computational Flow and Heat Transfer of a Row of Circular Jets Impinging on a Concave Surface
,”
Heat Mass Transfer
, 44(6), pp.
667
678
.
22.
Ling
,
J. P. C. W.
,
Ireland
,
P. T.
, and
Harvey
,
N. W.
,
2006
, “Measurement of Heat Transfer Coefficient Distributions and Flow Field in a Model of a Turbine Blade Cooling Passage With Tangential Injection,”
ASME
Paper GT2006-90352.
23.
Taslim
,
M. E.
, and
Bethka
,
D.
,
2008
, “
Experimental and Numerical Impingement Heat Transfer in an Airfoil Leading-Edge Cooling Channel With Cross-Flow
,”
ASME J. Turbomach.
,
131
(1), p. 011021.
24.
Xing
,
Y.
,
Spring
,
S.
, and
Weigand
,
B.
,
2010
, “
Experimental and Numerical Investigation of Heat Transfer Characteristics of Inline and Staggered Arrays of Impinging Jets
,”
ASME J. Heat Transfer
,
132
(9), p.
092201
.
25.
Liu
,
Z.
, and
Feng
,
Z. P.
,
2011
, “
Numerical Simulation on the Effect of Jet Nozzle Position on Impingement Cooling of Gas Turbine Blade Leading Edge
,”
Int. J. Heat Mass Transfer
,
54
(23–24), pp.
4949
4959
.
26.
Hossain
,
J.
,
Garrett
,
C.
,
Curbelo
,
A.
,
Harrington
,
J.
,
Wang
,
W. P.
, and
Kapat
,
J.
,
2016
, “Use of Rib Turbulators to Enhance Post-Impingement Heat Transfer for Curved Surface,”
ASME
Paper No. GT2016-56638.
27.
Parbat
,
S. N.
,
Siw
,
S. C.
, and
Chyu
,
M.
,
2016
, “Impingement Cooling in Narrow Rectangular Channel With Novel Surface Features,”
ASME
Paper No. GT2016-58084.
28.
Ekkad
,
S. V.
, and
Han
,
J. C.
,
2000
, “
A Transient Liquid Crystal Thermography Technique for Gas Turbine Heat Transfer Measurements
,”
Meas. Sci. Technol.
,
11
(7), pp.
957
968
.
29.
Kline
,
S. J.
, and
McClintock
,
F. A.
,
1953
, “
Describing Uncertainties in a Single Sample Experiment
,”
Mech. Eng.
,
75
, p. 36310.
You do not currently have access to this content.