Adsorption-based antifreeze system for loop heat pipes

A Review of Concentric Annular Heat Pipes

A detailed description of a concentric annular heat pipe (CAHP) operation is presented in low to moderate temperature ranges (50–200◦C). The steady-state response of a CAHP to various heat fluxes in the evaporator and condenser sections are discussed. Two-dimensional mathematical modeling of the fluid flow and heat transfer in the annular vapor space and the wicks are described. The fundamental...

Transport in Ultra-Thin Heat Pipes for Low Power Applications

Innovative wick design for multi-source, flat plate heat pipes

We present a novel micro-heat pipe wick design and fabrication technique to significantly boost the effective thermal conductivity of the heat pipe relative to the monolithic substrate material. Extensive porous flow modeling of the process has provided critical information on the key parameters and the resulting anisotropic wick designs have shown robust performance improvements. A methanol ch...

Upstreaming Mimics Capillarity in Geothermal Heat Pipes

The numerical technique called upstream differencing, applied to mobility terms in Darcy’s law for steam and liquid flow in the geothermal simulators TOUGH and MULKOM, is shown to lead to numerical boundary layers in the equations for steady vertical steam-liquid counterflow. These boundary layers are found to be very narrow, and to act in the same way as capillary boundary layers, providing re...

Wicking Study of Nanostructured Titania Surfaces for Flat Heat Pipes

We report a wicking material based on nanostructured TiO2 (NST) for the application of flat heat pipes. Heat pipes adopt wicking materials to achieve some unique functions that thermal siphons could not achieve[1], and they have found their applications as cooling systems in a wide variety of areas such as spacecraft and electronics. Different kinds of materials such as carbon nanotubes[2], nan...