This paper presents the detailed heat transfer coefficient and pressure drop through two different lattice structures suitable for use in the trailing edge of gas turbine airfoil. The lattice structures are located in the converging trailing edge channel with the coolant flow taking a 90 deg turn before entering the lattice structure. Two lattice structures were studied with one lattice structure having four-entry channels and the second lattice structure having two entry channels. Stationary tests were performed at four Reynolds numbers (4000 < Re < 20,000) based on the inlet subchannel diameter. The results show that the two-inlet-channel lattice structure produces higher values of heat transfer coefficient and lower values of pressure drop. The data from the converging lattice structures are compared with the published pin fin data which is the common standard for trailing edge applications. It is seen that the two-inlet-channel lattice structure produces average Nu/Nu0 values in the range of 2.1–3.4 compared to a value of 1.7–2.2 for a pin fin for the current set of Reynolds number. The thermal performance factor for the four-inlet-channel lattice structure is lower than the pin fin structure but the two-inlet-channel lattice structure provides comparable or higher thermal performance compared to a pin fin structure. The lattice structures also provide additional heat transfer area and structural rigidity to the trailing edge of the airfoil. Comparable or higher thermal performance and added structural rigidity can make the lattice structure a suitable alternative of pin fins in trailing edge applications.

References

References
1.
Metzger
,
D. E.
,
Berry
,
R. A.
, and
Bronson
,
J. P.
,
1982
, “
Developing Heat Transfer in Rectangular Ducts With Staggered Arrays of Short Pin Fins
,”
ASME J. Heat Transfer
,
104
, pp.
700
706
.10.1115/1.3245188
2.
Van Fossen
,
G. J.
,
1982
, “
Heat-Transfer Coefficients for Staggered Arrays of Short Pin Fins
,”
ASME J. Eng. Power
,
104
, pp.
268
274
.10.1115/1.3227275
3.
Metzger
,
D. E.
,
Fan
,
C. S.
, and
Haley
,
S. W.
,
1984
, “
Effects of Pin Shape and Array Orientation on Heat Transfer and Pressure Loss in Pin Fin Arrays
,”
ASME J. Eng. Gas Turbines Power
,
106
, pp.
252
257
.10.1115/1.3239545
4.
Chyu
,
M. K.
,
Hsing
,
Y. C.
,
Shih
,
T. I. P.
, and
Natarajan
,
V.
,
1999
, “
Heat Transfer Contributions of Pins and Endwall in Pin-Fin Arrays: Effects of Thermal Boundary Condition Modeling
,”
ASME J. Turbomach.
,
121
, pp.
257
263
.10.1115/1.2841309
5.
Hwang
,
J. J.
,
Lai
,
D. Y.
, and
Tsia
,
Y. P.
,
1999
, “
Heat Transfer and Pressure Drop in Pin-Fin Trapezoidal Ducts
,”
ASME J. Turbomach.
,
121
, pp.
264
271
.10.1115/1.2841310
6.
Chyu
,
M. K.
,
Oluyede
,
E. O.
, and
Moon
,
H. K.
, “
Heat Transfer on Convective Surfaces With Pin-Fins Mounted in Inclined Angles
,”
ASME
Paper No. GT2007-28138.10.1115/GT2007-28138
7.
Chyu
,
M. K.
,
Hsing
,
Y. C.
, and
Natarajan
,
V.
,
1998
, “
Convective Heat Transfer of Cubic Fin Arrays in a Narrow Channel
,”
ASME J. Turbomach.
,
120
, pp.
362
367
.10.1115/1.2841414
8.
Uzol
,
O.
, and
Camci
,
C.
,
2001
, “
Elliptical Pin Fins as an Alternative to Circular Pin Fins For Gas Turbine Airfoil Cooling Applications. Part 1: Endwall Heat Transfer and Total Pressure Loss Characteristics
,” ASME Paper No. GT-2001-0180.
9.
Bunker
,
R. S.
,
2004
, “
Latticework (Vortex) Cooling Effectiveness—Part 1: Stationary Channel Experiments
,”
ASME
Paper No. GT2004-54157.10.1115/GT2004-54157
10.
Goreloff
,
V.
,
Goychengerg
,
M.
, and
Malkoff
,
V.
,
1990
, “
The Investigation of Heat Transfer in Cooled Airfoils of Gas Turbines
,”
26th Joint Propulsion Conference
, AIAA Paper No. 90-2144.
11.
Acharya
,
S.
,
Zhou
,
F.
,
Lagrone
,
J.
,
Mahmood
,
G.
, and
Bunker
,
R. S.
,
2005
, “
Latticework (Vortex) Cooling Effectiveness: Rotating Channel Experiments
,”
ASME J. Turbomach.
,
127
, pp.
471
478
.10.1115/1.1860381
12.
Gillespie
,
D.
,
Ireland
,
P. T.
, and
Dailey
,
G. M.
,
2000
, “
Detailed Flow and Heat Transfer Coefficient Measurements in a Model of an Internal Cooling Geometry Employing Orthogonal Intersecting Channels
,” ASME Paper No. 2000-GT-653.
13.
Nagoga
,
G. P.
,
1996
,
Effective Methods of Cooling of Airfoils of High Temperature Gas Turbines
,
Moscow Aerospace Institute
,
Moscow, Russia
, p.
100
.
14.
Vedula
,
R. J.
, and
Metzger
,
D. E.
,
1991
, “
A Method for the Simultaneous Determination of Local Effectiveness and Heat Transfer Distributions in Three-Temperature Convection Situations
,” ASME Paper No. 91-GT-345.
15.
Metzger
,
D. E.
,
Bunker
,
R. S.
, and
Bosch
,
G.
,
1991
, “
Transient Liquid Crystal Measurement of Local Heat Transfer on a Rotating Disk With Jet Impingement
,”
ASME J. Turbomach.
,
113
, pp.
52
59
.10.1115/1.2927737
16.
Kline
,
S. J.
, and
McClintock
,
F. A.
,
1953
, “
Describing Uncertainties in Single-Sample Experiments
,”
Mech. Eng. Am. Soc. Mech. Eng.
,
75
, pp.
3
8
.
17.
Dittus
,
F. W.
, and
Boelter
,
L. M. K.
,
1930
,
Publications on Engineering
, Vol.
2
,
University of California at Berkeley
,
Berkeley, CA
, pp.
443
461
.
18.
Kays
,
W. M.
, and
Crawford
,
M. E.
,
1993
,
Convective Heat and Mass Transfer
,
3rd ed.
,
McGraw-Hill
,
New York
.
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