The implementation of high power density, multicore central and graphic processing units (CPUs and GPUs) coupled with higher clock rates of the high-end computing hardware requires enhanced cooling technologies able to attend high heat fluxes while meeting strict design constrains associated with system volume and weight. Miniature loop heat pipes (mLHP) emerge as one of the technologies best suited to meet all these demands. Nonetheless, operational problems, such as instable behavior during startup on evaporator side, have stunted the advent of commercialization. This paper investigates experimentally two types of mLHP systems designed for workstation CPUs employing disk shaped and rectangular evaporators, respectively. Since there is a strong demand for miniaturization in commercial applications, emphasis was also placed on physical size during the design stage of the new systems. One of the mLHP system investigated here is demonstrated to have an increased thermal performance at a reduced system weight. Specifically, it is shown that the system can reach a maximum heat transfer rate of 170 W with an overall thermal resistance of 0.12 K/W. The corresponding heat flux is 18.9 W/cm2, approximately 30% higher than that of larger size commercial systems. The studies carried out here also suggest that decreasing the thermal resistance between the heat source and the working fluid and maximizing the area for heat transfer are keys for obtaining an enhanced thermal performance.

References

References
1.
Hamilton
,
S.
, 2003, “
Intel Research Expands Moore’s Law
,”
IEEE Computer Society
,
36
, pp.
31
40
.
2.
Bar-Cohen
,
A.
, and
Iyengar
,
M.
, 2002, “
Design and Optimization of Air-Cooled Heat Sinks for Sustainable Development
,”
IEEE Trans. Compon. Packag. Technol.
,
25
(
4
), pp.
584
591
.
3.
Pastukhov
,
V. G.
,
Maydanik
,
Y. F.
, and
Vershinin
,
S. V.
, 2003, “
Miniature Loop Heat Pipes for Electronics Cooling
,”
Appl. Therm. Eng.
,
23
, pp.
1125
1135
.
4.
Maydanik
,
Y. F.
, 2005, “
Review: Loop Heat Pipes
,”
Appl. Therm. Eng.
,
25
, pp.
635
657
.
5.
Singh
,
R.
,
Akbarzadeh
,
A.
,
Dixon
,
C.
,
Mochizuki
,
M.
, and
Riehl
,
R. R.
, 2007, “
Miniature Loop Heat Pipe With Flat Evaporator for Cooling Computer CPUs
,”
IEEE Trans. Compon. Packag. Technol.
,
30
(
1
), pp.
42
49
.
6.
Pastukhov
,
V. G.
, and
Maydanik
,
Y. F.
, 2009, “
Active Coolers Based on Copper-Water LHPs for Desktop PC
,”
Appl. Therm. Eng.
,
29
, pp.
3140
3143
.
7.
Zalman CNPS9900 LED Intel Core i7 Compatible Heat Sink Review, http://www.frostytech.com.
8.
Pastukhov
,
V. G.
, and
Maydanik
,
Y. F.
, 2007, “
Low Noise Cooling System for PC on the Base of Loop Heat Pipes
,”
Appl. Therm. Eng.
,
27
, pp.
894
901
.
9.
Vershinin
,
S. V.
, and
Maydanik
,
Y. F.
, 2007, “
Investigation of Pulsations of the Operating Temperature in a Miniature Loop Heat Pipe
,”
Int. J. Heat Mass Transfer
,
50
, pp.
5235
5240
.
10.
Launay
,
S.
,
Satre
,
V.
, and
Bonjour
,
J.
, 2007, “
Parametric Analysis of Loop Heat Pipe Operation: A Literature Review
,”
Int. J. Therm. Sci.
,
46
, pp.
621
636
.
11.
Sung
,
B.
,
Choi
,
J.
,
Ki
,
J.
,
Yoo
,
J.
,
Seo
,
M.
, and
Kim
,
C.
, 2008, “
The Sintered Porous Metal Media Development and Measurement of LHP Systems for Electronic Cooling Device
,”
Proceedings of IMECE 2008
,
Boston
,
MA
, November 2–6 [CD-ROM].
12.
Reay
,
D.
, and
Kew
,
P.
, 2006,
Heat Pipes Theory, Design and Applications
,
5th ed.
,
Butterworth-Heinemann
,
United Kingdom
, pp.
126
139
.
13.
Rassamakin
,
B. M.
,
Gomelya
,
N. D.
,
Khairnasov
,
N. D.
, and
Rassamakina
,
N. V.
, 1997, “
Choice of the Effective Inhibitors of Corrosion and the Results of the Resources Tests of Steel and Aluminum Thermosyphon With Water
,”
Proceedings of the 10th International Heat Pipe Conference
,
Stuttgart
,
Germany
, September
21
25
.
14.
Gerrels
,
E. E.
, and
Larson
,
J. W.
, 1971, “
Brayton Cycle Vapor Chamber (Heat Pipe) Radiator Study
,”
General Electric Company
,
Philadelphia
,
NASA
, Report No. NASA CR-1677.
15.
Mochizuki
,
M.
,
Nguyen
,
T.
,
Mashiko
,
K.
,
Saito
,
Y.
,
Nguyen
,
T.
,
Wuttijumnong
,
V.
, and
Wu
,
X.
, 2004, “
Practical Application of Heat Pipe and Vapor Chamber for Cooling High Performance Personal Computer
,”
Proceedings of the 13th International Heat Pipe Conferencengs of the 13th International Heat Pipe Conference
,
Shanghai
,
China
, September 21–25, pp.
448
454
.
16.
Wang
,
J.
,
Huang
,
H.
, and
Chen
,
S.
, 2007, “
Experimental Investigations of Thermal Resistance of a Heat Sink With Horizontal Embedded Heat Pipes
,”
Int. Commun. Heat Mass Transfer
,
34
, pp.
958
970
.
You do not currently have access to this content.