Development of cryogenic loop heat pipes: A review and comparative analysis

Bai, Lizhan; Zhang, Lianpei; Lin, Guiping; Jiang, He; Wen, Dongsheng

doi:10.1016/j.applthermaleng.2015.06.010

Cited by 43 publications

(6 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Loop heat pipes (LHPs) are similar devices to HPs and employ the same capillary pumping process of working fluid as used in conventional HP but operate over much longer distances and/or against gravity by deploying a primary and secondary wick that is challenging to manufacture [26,[37][38][39]. Anderson et al constructed a cylindrical LHP utilising AM method where the casing, primary porous wick and secondary wick were manufactured in a single process eliminated knife-edge seal and bimetallic joints.…”

Section: Additive Manufacturing In Hpmentioning

confidence: 99%

Additive Manufacturing as a Solution to Challenges Associated with Heat Pipe Production

Szymański

Mikielewicz

2022

Materials

View full text Add to dashboard Cite

The aim of this review is to present the recent developments in heat pipe production, which respond to the current technical problems related to the wide implementation of this technology. A novel approach in HP manufacturing is to utilise hi-tech additive manufacturing techniques where the most complicated geometries are fabricated layer-by-layer directly from a digital file. This technology might be a solution to various challenges that exist in HP production, i.e., (1) manufacturing of complex or unusual geometries HPs; (2) manufacturing complicated and efficient homogenous wick structures with desired porosity, uniform pore sizes, permeability, thickness and where the pores are evenly distributed; (3) manufacturing a gravity friendly wick structures; (4) high customisation and production time; (5) high costs; (6) difficulties in the integration of the HP into a unit chassis that enables direct thermal management of heated element and decrease its total thermal resistance; (7) high weight and material use of the part; (8) difficulties in sealing; (9) deformation of the flat shape HPs caused by the high pressure and uneven distribution of stress in the casing, among others.

show abstract

Section: Additive Manufacturing In Hpmentioning

confidence: 99%

Additive Manufacturing as a Solution to Challenges Associated with Heat Pipe Production

Szymański

Mikielewicz

2022

Materials

View full text Add to dashboard Cite

show abstract

“…Generally, the operating temperature of spacecraft and electronic equipment is between 200-350 K [14]. According to the calculation formula of the Dunbar Parameters [15,16] (Eq. 1), the best working fluid in this temperature zone is ammonia.…”

Section: Al Wick Descriptionmentioning

confidence: 99%

Study of the heat transfer performance of a loop heat pipe with aluminum wick

Lin

Lei

2022

THERM SCI

View full text Add to dashboard Cite

This study used aluminum (Al) powder as a raw material to fabricate a wick for loop heat pipes (LHPs) by the powder metallurgy method and took advantage of the excellent corrosion resistance, low density and low cost of Al. The average pore diameter, porosity and permeability of the Al wicks were 9 ?m, 47.65%, and 2.1?10-13 m-2, respectively. Then, to verify the feasibility of the Al wick, it was installed into a LHP to test the heat transfer performance. The experimental results showed that the LHP could transport a heating load of 130 W with a thermal resistance of 0.04 KW-1 under horizontal condition. A steady-state LHP mathematical model was developed, and the numerical results were compared with the experimental data. The results show that the model data are consistent with the experimental data, which means that Al wicks are suitable for use in the case of a high heating load and light weight.

show abstract

“…In such a two-phase passive thermal control apparatus, extensive amounts of heat can be transferred with stable control of the heat source temperature. There has been a widespread effort to extend successful applications of LHPs to more common terrestrial applications [1][2][3][4][5][6][7][8] in order to develop more passive cooling systems, mainly based on liquid-vapour phase-change mechanisms to remove large heat fluxes. The electronic terrestrial applications benefit from the cooling advantages of LHPs (e.g., passive-electrical power-free, long-distance heat transfer, flexibility in design and assembly, robustness, antigravity capability, noise and vibration-free operation).…”

Section: Introductionmentioning

confidence: 99%

The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids

2021

View full text Add to dashboard Cite

This paper presents the results of experiments carried out on a specially designed experimental rig designed for the study of capillary pressure generated in the Loop Heat Pipe (LHP) evaporator. The commercially available porous structure made of sintered stainless steel constitutes the wick. Three different geometries of the porous wicks were tested, featuring the pore radius of 1, 3 and 7 µm. Ethanol and water as two different working fluids were tested at three different evaporator temperatures and three different installation charges. The paper firstly presents distributions of generated pressure in the LHP, indicating that the capillary pressure difference is generated in the porous structure. When installing with a wick that has a pore size of 1 μm and water as a working fluid, the pressure difference can reach up to 2.5 kPa at the installation charge of 65 mL. When installing with a wick that has a pore size of 1 μm and ethanol as a working fluid, the pressure difference can reach up to 2.1 kPa at the installation charge of 65 mL. The integral characteristics of the LHP were developed, namely, the mass flow rate vs. applied heat flux for both fluids. The results show that water offers larger pressure differences for developing the capillary pressure effect in the installation in comparison to ethanol. Additionally, this research presents the feasibility of manufacturing inexpensive LHPs with filter medium as a wick material and its influence on the LHP’s thermal performance.

show abstract

Development of cryogenic loop heat pipes: A review and comparative analysis

Cited by 43 publications

References 53 publications

Additive Manufacturing as a Solution to Challenges Associated with Heat Pipe Production

Additive Manufacturing as a Solution to Challenges Associated with Heat Pipe Production

Study of the heat transfer performance of a loop heat pipe with aluminum wick

The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids

Contact Info

Product

Resources

About