A number of analytical and numerical models have been developed by various researchers to predict the behavior of loop heat pipes (LHP). However, none of those models use the thin-film evaporation principles in the capillary structures to evaluate the local evaporative heat transfer coefficients. In this work, principles of the thin film evaporation are applied in a submodel and combined with our previously developed loop solver model to more accurately simulate the performance of a flat micro loop heat pipe. The resulting code predicts the heat removal capability, surface temperature, and local and average heat transfer coefficients at various applied heat loads. The results indicate that extremely high cross-sectionally averaged evaporative heat transfer coefficients can be achieved. The modeling results are verified by experimental data.

1.
Chi, S. W., 1976, “Heat pipe theory and practice,” Hemisphere Publishing Co., Washington, D. C.
2.
Dunn, P. D. and D. A. Reay, 1978, “Heat pipes,” 2nd Edition, Pergamon Press.
3.
Peterson, G. P., 1994, “An introduction to heat pipes: modeling, testing, and applications,” John Wiley & Sons, Inc., New York.
4.
Dockey
J. T.
, and
Peterson
G. P.
,
1994
, “
Experimental and Analytical Investigation of a Capillary Pumped Loop
,”
Journal of Thermophysics and Heat Transfer
, Vol.
8
, No.
3
, pp.
602
607
.
5.
Faghri, A., 1995, “Heat pipe science and technology,” Taylor & Francis, Inc., Washington DC.
6.
Maidanik, Y. F., S. V. Vershinin, V. F. Kholodov, and Y. F. Dolgirev, May 7, 1985, US Patent Number 4, 515, 209.
7.
Kiseev, V. M., Belonogov, A. G., and Pogorelov N. P., July 14-17, 1997, “Development of Two-Phase Loops with Capillary Pumps.” SAE 972482.
8.
Maidanik, Y. F., Ferchtater Y. G., and Goncharov K. A., 1991, “Capillary Pump Loop for the Systems of Thermal Regulation of Spacecraft,” ESA SP–324.
9.
Maidanik, Y., and Y. Fershtater, 1997, “Theoretical Basis and Classification of Loop Heat Pipes and Capillary Pumped Loops,” 10th International Heat Pipe Conference, Stuttgart, Germany.
10.
Ku, J., 1999, “Operating Characteristics of Loop Heat Pipes,” SAE Paper No. 1999-01-2007.
11.
Wolf, D. A., D. M. Donald, and A. L. Phillips, 1994, “Loop Heat Pipes-Their Performance and Potential”, SAE Paper No. 941575, 24th ICES, Germany.
12.
Phillips, A. L., J. E. Fale, N. J. Gernert, D. B. Sarraf, and W. J. Bienert, 1998, “Loop Heat Pipe Qualification for High Vibration and High-G Environments”, AIAA–98–0885.
13.
Hoelke
A.
,
Henderson
H. T.
,
Gerner
F. M.
, and
Kazmierczak
M.
,
1999
, “
Analysis of the Heat Transfer Capacity of a Micromachined Loop Heat Pipe
,”,
Proceedings of the ASME.
HTD Vol.
364
3
3
14.
Ghajar
M.
,
Darabi
J.
, and
Crews
N.
, Feb.
2005
, “
A hybrid CFD-mathematical model for simulation of a MEMS loop heat pipe for electronics cooling applications
,”
J. Micromech. Microeng.
,
15
, pp.
313
321
.
15.
Ghajar
M.
and
Darabi
,
2005
, “
Numerical modeling of evaporator surface temperature of a micro loop heat pipe at steady-state condition
,”
Journal of Micromechanics and Microengineering
, Vol.
15
, pp.
1963
1971
.
16.
Kaya, T., and Hoang, T., 1999, “Mathematical Modeling of Loop Heat Pipes,” AIAA Paper 99-0477.
17.
Hoang, T., and Kaya, T., 1999, “Mathematical Modeling of Loop Heat Pipes with Two-Phase Pressure Drop,” AIAA Paper 99-3448.
18.
Wayner
P. C.
,
Kao
Y. K.
and
LaCroix
L. V.
,
1976
, “
The interline heat transfer coeffcinet of an evaporative thin film
,”
Int. J. Heat Mass Transfer
, Vol.
19
, pp.
487
492
.
19.
Derjaguin, B. V. and Zorin, Z. M., 1957, “Optical study of the adsorption and surface condensation of vapors in the vicinity of saturation on a smooth surface,” 2nd Int’l Congr. Surf. Activity (London), Vol. 2.
20.
Derjaguin, B. V., Nerpin, S. V., and Churayev, N. V., 1965, “Effect of film transfer upon evaporation of liquids from capillaries,” Bulletin Rilem, 29.
21.
Truong
J. G.
, and
Wayner
P. C.
,
1987
, “
Effects of capillary and van der Waals dispersion forces on equilibrium profile of a wetting liquid: Theory and experiment
,”
J. Chem. Phys.
87
(
7)
, pp.
4180
4188
.
22.
Derjaguin, B. V., 1955, Kolloidnyi Zhurnal (English Translation), 17, p. 191.
23.
Derjaguin
B. V.
,
Rabinovich
Y. I.
and
Churaev
N. V.
,
1978
, “
Direct measurement of molecular forces
,”
Nature
,
272
, p.
313
313
.
24.
Dzyaloshinskii
I. E.
,
Lifshitz
E. M.
, and
Pitaevskii
L. V.
,
1961
, “
The general theory of van der Waals forces
,”
Adv. Phys.
10
, p.
165
165
.
25.
deGennes, P. G., 1985, “Wetting: statics and dynamics,” Reviews of Modern Physics, 57 (3), Part 1, July.
26.
Stephan
P. C.
and
Busse
C. A.
,
1992
, “
Analysis of heat transfer coefficient of grooved heat pipe evaporator walls
,”
Int. J. Heat Mass Transfer
,
35
(
2)
, pp.
383
391
.
27.
Sartre
V.
,
Zaghdouni
MC
,
Lallemand
M.
,
2000
, “
Effect of interfacial phenomena on evaporative heat transfer in micro heat pipes
,”
Int. J. Therm. Sci.
,
39
, pp.
498
504
.
28.
Chin-Chun
Hsu
,
Shung-Wen
Kang
, and
Tung-Fu
Hou
,
2005
, “
Performance Testing of Micro Loop Heat Pipes
,”
Tamkang Journal of Science and Engineering
, Vol.
8
, No
2
, pp.
123
132
.
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