Heat and Mass Transfer

, 47:933 | Cite as

Effect of pore size distribution in bidisperse wick on heat transfer in a loop heat pipe

  • Fang-Chou Lin
  • Bing-Han Liu
  • Chun-Chia Juan
  • Yau-Ming ChenEmail author


The purpose of this article is to experimentally investigate the effect of different pore size distributions in bidisperse wicks upon the heat transfer performance in a LHP. Three bidisperse wicks and one monoporous wick were tested in a loop heat pipe. The pore size distributions of the bidisperse wicks were measured, and the results reflected the three different large/small pore size ratios. The experiments showed that the maximum heat load of the monoporous wick reached about 400 W; and the three bidisperse wicks showed improvements on the maximum heat load up to 570 W. For the monoporous wick, the evaporator heat transfer coefficients of 10 kW/m2 K and total thermal resistance of 0.19°C/W were achieved at a high heat load of 400 W. For the better bidisperse wick, the evaporator heat transfer coefficients could attain about 23 kW/m2 K and total thermal resistance of 0.13°C/W. The results also indicated that a smaller cluster size in a bidisperse structure created a small pore size ratio. It was also found that the bidisperse wick with smaller clusters had a better enhancement in terms of the evaporator heat transfer coefficient.


Heat Transfer Coefficient Pore Size Distribution Heat Pipe Heat Load Critical Heat Flux 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols


Area, m2


Wick diameter, m


Heat transfer coefficient, W/m2K


Permeability, m2


Length, m

\( \dot{m} \)

Mass flow rate, kg/s

\( \Updelta P \)

Pressure drop, Pa


Applied heat load, W


Total thermal resistance, K/W


Temperature, K

Greek symbols

\( \rho \)

Density, kg/m3

\( \mu \)

Viscosity, Pa s

















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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Fang-Chou Lin
    • 1
  • Bing-Han Liu
    • 1
  • Chun-Chia Juan
    • 1
  • Yau-Ming Chen
    • 1
    Email author
  1. 1.Department of Mechanical EngineeringNational Taiwan UniversityTaipeiTaiwan

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