With the advance of direct metal laser sintering (DMLS), also generically referred to as additive manufacturing (AM), novel geometric features of internal channels for gas turbine cooling can be achieved beyond those features using traditional manufacturing techniques. There are many variables, however, in the DMLS process that affect the final quality of the part. Of most interest to gas turbine heat transfer designers are the roughness levels and tolerance levels that can be held for the internal channels. This study investigates the effect of DMLS build direction and channel shape on the pressure loss and heat transfer measurements of small-scale channels. Results indicate that differences in pressure loss occur between the test cases with differing channel shapes and build directions, while little change is measured in heat transfer performance.

References

References
1.
Simchi
,
A.
,
Petzoldt
,
F.
, and
Pohl
,
H.
,
2003
, “
On the Development of Direct Metal Laser Sintering for Rapid Tooling
,”
J. Mater. Process. Technol.
,
141
(
3
), pp.
319
328
.
2.
Khaing
,
M. W.
,
Fuh
,
J. Y. H.
, and
Lu
,
L.
,
2001
, “
Direct Metal Laser Sintering for Rapid Tooling: Processing and Characterisation of EOS Parts
,”
J. Mater. Process. Technol.
,
113
(
1–3
), pp.
269
272
.
3.
Song
,
Y.-A.
, and
Koenig
,
W.
,
1997
, “
Experimental Study of the Basic Process Mechanism for Direct Selective Laser Sintering of Low-Melting Metallic Powder
,”
CIRP Ann. Manuf. Technol.
,
46
(
1
), pp.
127
130
.
4.
Calignano
,
F.
,
Manfredi
,
D.
,
Ambrosio
,
E. P.
,
Iuliano
,
L.
, and
Fino
,
P.
,
2013
, “
Influence of Process Parameters on Surface Roughness of Aluminum Parts Produced by DMLS
,”
Int. J. Adv. Manuf. Technol.
,
67
(
9–12
), pp.
2743
2751
.
5.
Senthilkumaran
,
K.
,
Pandey
,
P. M.
, and
Rao
,
P. V. M.
,
2009
, “
Influence of Building Strategies on the Accuracy of Parts in Selective Laser Sintering
,”
Mater. Des.
,
30
(
8
), pp.
2946
2954
.
6.
Delgado
,
J.
,
Ciurana
,
J.
, and
Rodríguez
,
C. A.
,
2012
, “
Influence of Process Parameters on Part Quality and Mechanical Properties for DMLS and SLM With Iron-Based Materials
,”
Int. J. Adv. Manuf. Technol.
,
60
(
5–8
), pp.
601
610
.
7.
Simonelli
,
M.
,
Tse
,
Y. Y.
, and
Tuck
,
C.
,
2014
, “
Effect of the Build Orientation on the Mechanical Properties and Fracture Modes of SLM Ti–6Al–4V
,”
Mater. Sci. Eng. A
,
616
, pp.
1
11
.
8.
Manfredi
,
D.
,
Calignano
,
F.
,
Krishnan
,
M.
,
Canali
,
R.
,
Ambrosio
,
E. P.
, and
Atzeni
,
E.
,
2013
, “
From Powders to Dense Metal Parts: Characterization of a Commercial AlSiMg Alloy Processed Through Direct Metal Laser Sintering
,”
Materials
,
6
(
3
), pp.
856
869
.
9.
Ventola
,
L.
,
Robotti
,
F.
,
Dialameh
,
M.
,
Calignano
,
F.
,
Manfredi
,
D.
,
Chiavazzo
,
E.
, and
Asinari
,
P.
,
2014
, “
Rough Surfaces With Enhanced Heat Transfer for Electronics Cooling by Direct Metal Laser Sintering
,”
Int. J. Heat Mass Transfer
,
75
, pp.
58
74
.
10.
Wong
,
M.
,
Owen
,
I.
,
Sutcliffe
,
C. J.
, and
Puri
,
A.
,
2009
, “
Convective Heat Transfer and Pressure Losses Across Novel Heat Sinks Fabricated by Selective Laser Melting
,”
Int. J. Heat Mass Transfer
,
52
(
1–2
), pp.
281
288
.
11.
Manglik
,
R. M.
, and
Bergles
,
A. E.
,
1995
, “
Heat Transfer and Pressure Drop Correlations for the Rectangular Offset Strip Fin Compact Heat Exchanger
,”
Exp. Therm. Fluid Sci.
,
10
(
2
), pp.
171
180
.
12.
Bunker
,
R. S.
,
2013
, “
Gas Turbine Cooling: Moving From Macro to Micro Cooling
,”
ASME
Paper No. GT2013-94277.
13.
Helmer
,
D. B.
,
2014
, “
Modified Transient Infrared Methodology for Leading Edge Impingement Measurements
,”
ASME
Paper No. GT2014-25884.
14.
Kinel
,
M.
,
Utriainen
,
E.
, and
Jaksch
,
P.
,
2014
, “
An Alternate Experimental Method for Establishing Detailed Internal Heat Transfer Coefficient Distributions of Complex Cooling Geometries Using IR Thermography
,”
ASME
Paper No. GT2014-25616.
15.
EOS
,
2011
, Basic Training EOSINT M 280, Electro Optical Systems GmbH, Munich, Germany.
16.
Reinhart
,
C.
,
2011
, “Industrial CT & Precision,” Volume Graphics GmbH, Heidelberg, Germany.
17.
DeGarmo
,
P. E.
,
Black
,
J. T.
, and
Kohser
,
R. A.
,
2003
,
Materials and Processes in Manufacturing
,
Wiley
,
Hoboken, NJ
.
18.
Stimpson
,
C. K.
,
Snyder
,
J. C.
,
Thole
,
K. A.
, and
Mongillo
,
D.
,
2015
, “
Roughness Effects on Flow and Heat Transfer for Additively Manufactured Channels
,”
ASME
Paper No. GT2015-43940.
19.
Cooper
,
D. E.
,
Stanford
,
M.
,
Kibble
,
K. A.
, and
Gibbons
,
G. J.
,
2012
, “
Additive Manufacturing for Product Improvement at Red Bull Technology
,”
Mater. Des.
,
41
, pp.
226
230
.
20.
Weaver
,
S. A.
,
Barringer
,
M. D.
, and
Thole
,
K. A.
,
2011
, “
Microchannels With Manufacturing Roughness Levels
,”
ASME J. Turbomach.
,
133
(
4
), p.
041014
.
21.
Figliola
,
R. S.
, and
Beasley
,
D. E.
,
2005
,
Theory and Design for Mechanical Measurements
,
Wiley
,
Hoboken, NJ
.
22.
Huang
,
K.
,
Wan
,
J. W.
,
Chen
,
C. X.
,
Li
,
Y. Q.
,
Mao
,
D. F.
, and
Zhang
,
M. Y.
,
2013
, “
Experimental Investigation on Friction Factor in Pipes With Large Roughness
,”
Exp. Therm. Fluid Sci.
,
50
, pp.
147
153
.
23.
Dai
,
B.
,
Li
,
M.
, and
Ma
,
Y.
,
2014
, “
Effect of Surface Roughness on Liquid Friction and Transition Characteristics in Micro- and Mini-Channels
,”
Appl. Therm. Eng.
,
67
(
1–2
), pp.
283
293
.
24.
Gnielinski
,
V.
,
1976
, “
New Equations for Heat and Mass-Transfer in Turbulent Pipe and Channel Flow
,”
Int. Chem. Eng.
,
16
(
2
), pp.
359
368
.
25.
Norris
,
R. H.
,
1971
, “
Some Simple Approximate Heat Transfer Correlations for Turbulent Flow in Ducts With Surface Roughness
,”
Augmentation of Convection Heat and Mass Transfer
,
American Society of Mechanical Engineers
,
New York
.
You do not currently have access to this content.