Abstract
An experimental study and theoretical analysis of heat transfer performance of a sintered heat pipe radiator that implemented in a 50 L domestic semiconductor refrigerator have been conducted to examine the effect of inclination angle, combined with a minimum entropy generation analysis. The experiment results suggest that inclination angle has influences on both the evaporator and condenser section, and the performance of the heat pipe radiator is more sensitive to the inclination change in negative inclined than in positive inclined position. When the heat pipe radiator is in negative inclination angle position, large amplitude of variation on the thermal resistance of this heat pipe radiator is observed. As the thermal load is below 58.89 W, the influence of inclination angle on the overall thermal resistance is not that apparent as compared to the other three thermal loads. Thermal resistance of heat pipe radiator decreases by 82.86 % in inclination of 60° at the set of 138.46 W, compared to horizontal position. Based on the analysis results in this paper, in order to achieve a better heat transfer performance of the heat pipe radiator, it is recommended that the heat pipe radiator be mounted in positive inclination angle positions (30°–90°), where the condenser is above the evaporator.
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Abbreviations
- K :
-
Permeability (m−2)
- r :
-
Radius (m)
- l :
-
Effective length (m)
- \(\dot{m}\) :
-
Mass flow rate (m3/s)
- T :
-
Temperature (K)
- Q :
-
Heat transfer rate (W)
- k :
-
Thermal conductivity (W/m K)
- A :
-
Area (m2)
- ΔP :
-
Pressure drop (Pa)
- L :
-
Latent heat of vaporization (kJ/kg)
- q :
-
Heat flux (W/m2)
- R :
-
Thermal resistance (K/W)
- ρ :
-
Density (kg/m3)
- φ :
-
Inclination angle (degree)
- μ :
-
Dynamic viscosity (Pa s)
- θ :
-
Solid–liquid contact angle
- ɛ :
-
Wick porosity
- σ :
-
Liquid–vapor surface tension (N/m)
- η :
-
Specific value
- e :
-
Evaporation section
- c :
-
Condensation section
- l :
-
Liquid region
- v :
-
Vapor region
- a :
-
Adiabatic section
- s :
-
Solid structure
- w :
-
Wick structure
- g :
-
Gravity
- C :
-
Wick capillary
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Acknowledgments
This research was supported by the Guangdong Province Science and Technology Program (No. 2013B090600022, 2014KQNCX175), and the Guangzhou Science and Technology Program (No. 201508010045).
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Cong, L., Qifei, J. & Wu, S. Experimental and theoretical analysis on the effect of inclination on metal powder sintered heat pipe radiator with natural convection cooling. Heat Mass Transfer 53, 581–589 (2017). https://doi.org/10.1007/s00231-016-1840-3
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DOI: https://doi.org/10.1007/s00231-016-1840-3