Development of LHPs with ceramic wick

• Published in: Applied thermal engineering Vol. 30; no. 13; pp. 1784 - 1789
• Main Authors: Santos, Paulo H.D., Bazzo, Edson, Becker, Susanne, Kulenovic, Rudi, Mertz, Rainer
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-09-2010; Elsevier
• Subjects: Acetone; Applied sciences; Assembly; Ceramic porous wick; Ceramics; Energy; Energy. Thermal use of fuels; Evaporators; Exact sciences and technology; Heat transfer; Inclination; LHP; Porosity; Steady state; Theoretical studies. Data and constants. Metering; Water; Wicks; Water; Ceramic porous wick; LHP; Acetone; Heat pipe; Permeability; Heated pipe; Steady state; Stainless steel; Evaporator; Porosity; Plastics; Performance; Ceramic materials; Heat sink
• ISSN: 1359-4311
• DOI: 10.1016/j.applthermaleng.2010.04.010

The ceramic porous wick is proposed as an alternative to wicks made of metal and plastic for Loop Heat Pipes (LHP) applications. Performance tests of two LHPs using acetone and water as working fluids were carried out for power inputs up to 25
W. The evaporators have a stainless steel cylindrical assembly, with 80
mm of length and 10
mm of inner diameter. The ceramic porous wick has 50% of porosity, 1–3
μm of pore radius distribution and a permeability of about 35
×
10
−15
m
2. The active zone length of the evaporators is 25
mm. For a limited operation temperature of 100
°C, the LHPs were able to transfer up to 25 and 15
W using acetone and water, respectively, at steady state condition. An operation analysis concerning the effects of the LHP inclination, the heat sink temperature and LHP thermal resistances is also presented. Despite the relative good performance of the LHPs, further researches are still required taking into account changes related to properties of the ceramic porous wick in particular and improvements in the whole LHP design in general.