Abstract

In an electronic circuit of laptops, supercomputers with multiple central processing units, spacecraft etc., it is required to arrange the cooling system for multiple heat loads in the smallest possible space in view of power-saving opportunities. In the present study, the experimental investigations are carried out on a wickless multi-branch heat pipe in gravity-assisted mode with two evaporators and one condenser on each of the individual branches. The start-up and dynamic characteristics were studied with different filling ratios (range, 40–70%), with equal heat loads (range, 0–200 W) and unequal heat loads (range, 0–100 W) on evaporators. The results are analyzed in terms of temperature variation in axial direction, thermal resistance, and heat transfer coefficient for a multi-branch thermosiphon heat pipe (MBTHP). It was found that the optimal filling ratio depends on the applied heat load under tested conditions. In a thermosiphon mode, the heat pipe was capable of transporting a maximum heat load of 210 W and maximum heat flux of 20.31 W/cm2 with the maximum evaporator temperature lower than 100 °C. The minimum wickless thermal resistance of heat pipe was found to be 0.21 °C/W at 50% filling ratio and 160 W and maximum total heat transfer coefficient was found as 6.33 k W/m2 °C.

References

1.
Garimella
,
S. V.
,
Fleischer
,
A. S.
,
Murthy
,
J. Y.
, and
Keshavarzi
,
A.
,
2008
, “
Thermal Challenges in Next-Generation Electronic Systems
,”
IEEE Trans. Compon. Packag. Manuf. Technol.
,
31
(
4
), pp.
801
815
.
2.
Xianping
,
C.
,
Huaiyu
,
Y.
,
Xuejun
,
F.
,
Tianling
,
R.
, and
Guoqi
,
Z.
,
2016
, “
A Review of Small Heat Pipes for Electronics
,”
Appl. Therm. Eng.
,
96
, pp.
1
17
.
3.
Reay
,
D.
, and
Kew
,
P.
,
2006
,
Heat Pipes Theory, Design and Applications
, 5th ed.,
Elsevier
,
New York
.
4.
Zohuri
,
B.
,
2016
,
Heat Pipe Design and Technology
, 2nd ed.,
Springer
,
New York
.
5.
Moon
,
S. H.
,
Hwang
,
G.
,
Ko
,
S. C.
, and
Kim
,
Y. T.
,
2004
, “
Experimental Study on the Thermal Performance of Micro-heat Pipe With Cross-section of Polygon
,”
Micro Electron. Reliab.
,
44
(
2
), pp.
315
321
.
6.
Hoang
,
T. T.
, and
Ku
,
J.
,
2008
, “
Heat and Mass Transfer in Loop Heat Pipes
,”
Proceedings of the ASME 2003 Heat Transfer Summer Conference
, Vol.
2
,
Las Vegas, NV
,
July 21–23, 2003
, pp.
485
493
, ASME Paper No. HT2003-47366.
7.
Chi
,
S. W.
,
1976
,
Heat Pipe Theory and Practice: A Sourcebook
,
Hemisphere Publishing
,
Washington, DC
, pp.
33
78
.
8.
Wang
,
Y.
,
Wang
,
B.
,
Zhu
,
K.
,
Li
,
H.
,
He
,
W.
, and
Liu
,
S.
,
2018
, “
Energy Saving Potential of Using Heat Pipes for CPU Cooling
,”
Appl. Therm. Eng.
,
143
, pp.
630
638
.
9.
Tang
,
H.
,
Tang
,
Y.
,
Li
,
J.
,
Sun
,
Y.
,
Liang
,
G.
, and
Peng
,
R.
,
2018
, “
Experimental Investigation of the Thermal Performance of Heat Pipe With Multi-heat Source and Double-End Cooling
,”
Appl. Therm. Eng.
,
131
, pp.
159
166
.
10.
Desai
,
A. N.
,
Singh
,
V. K.
, and
Patel
,
R. N.
,
2019
, “
Effect of Geometrical Parameters on the Thermal Performance of Ammonia Based Trapezoidal-Shaped Axial Grooved Heat Pipe
,”
ASME J. Heat Transfer-Trans. ASME
,
141
(
12
), p.
121801
.
11.
Boo
,
H.
, and
Gon Kim
,
H.
,
2017
, “
Experimental Study on the Performance Characteristics of a Cylindrical Heat Pipe Having a Screen Wick Subject to Multiple Heat Sources
,”
Appl. Therm. Eng.
,
126
, pp.
1209
1215
.
12.
Han
,
X.
,
Wang
,
Y.
, and
Liang
,
Q.
,
2018
, “
Investigation of the Thermal Performance of a Novel Flat Heat Pipe Sink With Multiple Heat Sources
,”
Int. Commun. Heat Mass Transfer
,
94
, pp.
71
76
.
13.
Liang
,
C.
,
Patel
,
D. R.
, and
Shelat
,
M. R.
,
2018
, “
Mathematical Modelling of a Long Finned Tube Heating and Cooling in a Multizone Furnace
,”
ASME J. Therm. Sci. Eng. Appl.
,
10
(
5
), p.
051022
.
14.
Fourgeaud
,
L.
,
Mari
,
R.
,
Dupont
,
V.
, and
Figus
,
C.
,
2018
, “
Experimental Investigations of a Multi-Source Loop Heat Pipe for Electronics Cooling
,”
Proceedings of the Joint 19th IHPC and 13th IHPS
,
Pisa, Italy
,
June 2017
, pp.
10
14
.
15.
Pastukhov
,
V. G.
, and
Maydanik
,
Y. F.
,
2018
, “
Development and Tests of a Loop Heat Pipe With Several Separate Heat Sources
,”
Appl. Therm. Eng.
,
144
, pp.
165
169
.
16.
Okutani
,
S.
,
Nagano
,
H.
,
Okazaki
,
S.
,
Ogawa
,
H.
, and
Nagai
,
H.
,
2014
, “
Operating Characteristics of Multiple Evaporators and Multiple Condensers Loop Heat Pipe With Polytetrafluoroethylene Wicks
,”
J. Electron. Cool. Therm. Control
,
4
(
1
), pp.
22
32
.
17.
Gunnasegaran
,
P.
,
Abdullah
,
M. Z.
, and
Shuaib
,
N. H.
,
2013
, “
Influence of Nanofluid on Heat Transfer in a Loop Heat Pipe
,”
Int. Commun. Heat Mass Transfer
,
47
, pp.
82
91
.
18.
Wanga
,
G.
,
Quana
,
Z.
,
Zhaoa
,
Y.
, and
Wanga
,
H.
,
2018
, “
Performance of a Flat-Plate Micro Heat Pipe at Different Filling Ratios and Working Fluids
,”
Appl. Therm. Eng.
,
146
, pp.
459
468
.
19.
Mahdavi
,
M.
,
Tiaria
,
S.
,
Schampheleireb
,
S. D.
, and
Qiuc
,
S.
,
2018
, “
Experimental Study of the Thermal Characteristics of a Heat Pipe
,”
Exp. Therm. Fluid. Sci.
,
93
, pp.
292
304
.
20.
Sedighi
,
E.
,
Amarloo
,
A.
, and
Shafii
,
M. B.
,
2018
, “
Experimental Investigation of the Thermal Characteristics of Single-Turn Pulsating Heat Pipes With an Extra Branch
,”
Int. J. Therm. Sci.
,
134
, pp.
258
268
.
21.
Cai
,
Y.
,
Li
,
Z.
,
Zhai
,
J.
,
Tang
,
Y.
, and
Yu
,
B.
,
2017
, “
Experimental Investigation on a Novel Multi-branch Heat Pipe for Multi-heat Source Electronics
,”
Int. J. Heat Mass Transfer
,
104
, pp.
467
477
.
22.
Zhong
,
G.
,
Ding
,
X.
,
Tang
,
Y.
,
Yu
,
S.
,
Chen
,
G.
,
Tang
,
H.
, and
Li
,
Z.
,
2018
, “
Various Orientations Research on Thermal Performance of Novel Multi-branch Heat Pipes With Different Sintered Wicks
,”
Energy Convers. Manage.
,
166
, pp.
512
521
.
23.
Chantasiriwan
,
S.
,
2015
, “
Effects of Cooling Water Flow Rate and Temperature on the Performance of a Multiple-Effect Evaporator
,”
Chem. Eng. Commun.
,
202
(
5
), pp.
622
628
.
24.
Cengel
,
Y.
, and
Boles
,
M.
,
2017
,
Thermodynamics: An Engineering Approach (SIE)
,
McGraw-Hill Publication
,
India
.
25.
Kline
,
S. J.
,
1985
, “
The Purposes of Uncertainty Analysis
,”
ASME J. Fluids Eng.
,
107
(
2
), pp.
153
160
.
26.
Kim
,
K. M.
,
Jeong
,
Y. S.
,
Kim
,
I. G.
, and
Bang
,
I. C.
,
2015
, “
Comparison of Thermal Performances of Water-Filled, SiC Nanofluid-Filled and SiC Nanoparticles-Coated Heat Pipes
,”
Int. J. Heat Mass Transfer
,
88
, pp.
862
871
.
27.
Valentin
,
G.
,
Sulaiman
,
A.
, and
Hussam
,
J.
,
2019
, “
Nucleate Pool Boiling Heat Transfer in Wickless Heat Pipes (Two-Phase Closed Thermosiphon): A Critical Review of Correlations
,”
Ther. Sci. Eng. Prog.
,
13
, p.
100384
.
28.
Zhang
,
H. Y.
,
Mui
,
Y. C.
, and
Tarin
,
M.
,
2010
, “
Analysis of Thermoelectric Cooler Performance for High Power Electronic Packages
,”
Appl. Therm. Eng.
,
30
(
6–7
), pp.
561
568
.
29.
Zhu
,
K.
,
Li
,
X.
,
Wang
,
Y.
,
Chen
,
X.
, and
Li
,
H.
,
2017
, “
Dynamic Performance of Loop Heat Pipes for Cooling of Electronics
,”
Proceedings of the 9th International Conference on Applied Energy, ICAE Energy Procedia
,
Cardiff, UK
,
Aug. 21–24
, Vol.
142
, pp.
4163
4168
.
30.
Joseph
,
S.
,
2016
, “
Length Effect on Entrainment Limitation of Vertical Wickless Heat Pipe
,”
Int. J. Heat Mass Transfer
,
101
, pp.
373
378
.
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