Review of liquid metal heat pipe work at Los Alamos

Experimental study has been conducted for multiscale characterization of liquid metal (Na) transport within a heat pipe using a neutron imaging technique. Feasibility of nonintrusive imaging of liquid sodium contained inside a nickel alloy heat pipe has been examined for the imaging resolution, exposure time requirements, background noises, and other basic considerations associated with neutron beam scattering. Preliminary results of neutron imaging show fairly acceptable feasibility of neutron imaging of liquid sodium contained inside an alloy jacket. Furthermore, challenges are identified to enhance the spatial and thermal resolutions in order to achieve more physically demanding imaging of the liquid metal thermal transport behaviors.

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Experimental Investigation of Oscillating Heat Pipe With Hybrid Fluids of Liquid Metal and Water

Journal of Heat Transfer ◽

10.1115/1.4043620 ◽

2019 ◽

Vol 141 (7) ◽

Cited By ~ 2

Author(s):

Tingting Hao ◽

Hongbin Ma ◽

Xuehu Ma

Keyword(s):

Heat Transfer ◽

Liquid Metal ◽

Heat Pipe ◽

Heat Input ◽

Heat Transfer Performance ◽

Pure Water ◽

Experimental Results ◽

Working Fluid ◽

Transfer Performance ◽

Oscillating Heat Pipe

A new oscillating heat pipe (OHP) charged with hybrid fluids can improve thermal performance. The key difference in this OHP is that it uses room temperature liquid metal (Galinstan consisting of gallium, indium, and tin) and water as the working fluid. The OHP was fabricated on a copper plate with six turns and a 3 × 3 mm2 cross section. The OHP with hybrid fluids as the working fluid was investigated through visual observation and thermal measurement. Liquid metal was successfully driven to flow through the OHP by the pressure difference between the evaporator and the condenser without external force. Experimental results show that while added liquid metal can increase the heat transport capability, liquid metal oscillation amplitude decreases as the filling ratio of liquid metal increases. Visualization of experimental results show that liquid metal oscillation position and velocity increase as the heat input increases. Oscillating motion of liquid metal in the OHP significantly increases the heat transfer performance at high heat input. The lowest thermal resistance of 0.076 °C/W was achieved in the hybrid fluids-filled OHP with a heat input of 420 W. We experimentally demonstrated a 13% higher heat transfer performance using liquid metal as the working fluid compared to an OHP charged with pure water.

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Operation of the liquid-metal heat pipe in applications involving aerodynamic heating

10.2514/6.1996-478 ◽

1996 ◽

Author(s):

Won Chang ◽

Jeffrey Brown

Keyword(s):

Liquid Metal ◽

Heat Pipe ◽

Aerodynamic Heating

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Radiant heating tests of several liquid metal heat-pipe sandwich panels

10.2514/6.1983-319 ◽

1983 ◽

Cited By ~ 4

Author(s):

C. CAMARDA ◽

A. BASIULIS

Keyword(s):

Liquid Metal ◽

Heat Pipe ◽

Sandwich Panels ◽

Radiant Heating

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High Flux Value Micro-Heat Pipe Arrays

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2010dpc-wp21 ◽

2010 ◽

Vol 2010 (DPC) ◽

pp. 001760-001807

Author(s):

Daniel K. Harris ◽

Robert Dean ◽

Ashish Palkar ◽

Gary Wonacott

Keyword(s):

Liquid Metal ◽

Heat Pipe ◽

Experimental Work ◽

Performance Enhancement ◽

Performance Testing ◽

Heat Pipes ◽

Working Fluid ◽

Working Fluids ◽

Micro Heat Pipe ◽

Micro Heat Pipes

The concept of heat pipes was introduced by R.S.Gaugler in 1940s and Cotter first introduced the idea of “micro” heat pipes in 1984. Cotter in his paper, defined the micro heat pipe as being one in which the mean curvature of the vapor-liquid interface is comparable in magnitude to the reciprocal of the hydraulic radius of the total flow channel. The Micro Heat Pipes (MHPs) work efficiently through the use of two-phase heat transfer. Various working fluids have been tried in combination with various substrate materials. In this experimental work the main focus was to study the behavior of liquid metal filled MHPs made from silicon as the substrate material. Specially designed MHPs were assembled and charged with mercury as the working fluid. A special test setup was designed and built for the experimental work and the response of the MHPs to the controlled increment in the input power is presented. A number of experiments were carried out on the specimen MHPs to determine their effective thermal conductivity, the variation of the temperature along the axial length and the performance enhancement factor. Effective thermal conductivities as high as 900 W/m-K with a silicon equivalence of 6 were achieved with the liquid metal MHP. Based on the results from the various performance testing parameters, it was observed that the liquid metal charged MHPs performed substantially better than conventional MHPs filled with organic working fluids. The limitations and the possible methods of improving the performance of the MHPs are discussed.

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