The miniaturization boiling (micro-bubble emission boiling [MEB]) phenomenon, with a high heat removal capacity that contributes considerably to the cooling of the divertor of the nuclear fusion reactor, was discovered in the early 1980s. Extensive research on MEB has been performed since its discovery. However, the progress of the application has been delayed because the generation mechanism o...

Evaporation and explosive boiling of ultra-thin liquid film are of great significant fundamental importance for both science and engineering applications. The evaporation and explosive boiling of ultra-thin liquid film absorbed on an aluminum nanostructure solid wall are investigated by means of molecular dynamics simulations. The simulated system consists of three regions: liquid argon, vapor ...

Experiments were performed to examine the effects of body force on flow boiling CHF. FC-72 was boiled along one wall of a transparent rectangular flow channel that permitted photographic study of the vapor-liquid interface just prior to CHF. High-speed video imaging techniques were used to identify dominant CHF mechanisms corresponding to different flow orientations and liquid velocities. Six d...

We report the counterintuitive mechanism of increasing boiling heat transfer by incorporating low-conductivity materials at the interface between the surface and fluid. By embedding an array of non-conductive lines into a high-conductivity substrate, in-plane variations in the local surface temperature are created. During boiling the surface temperature varies spatially across the substrate, al...

Heat fluxes in IC chips and other electronics equipment have reached the current limits of air-cooling technology. Some of the applications require heat fluxes well beyond the limit of 100 W/cm2, thus demanding advanced cooling solutions. Liquid cooling technology has also received attention as the advances in single-phase liquid cooling in microchannels have shown considerable promise. The ext...

Ahstract-Experiments are performed to develop a fundamental understanding of boiling incipience in wavy free-falling turbulent liquid films. Incipience conditions are measured and correlated for water and a fluorocarbon (FC-72) liquid. Incipience in water films is influenced by turbulent eddies and, to a larger extent, by interfacial waves. A new approach to predicting incipience in water and o...

When focused ultrasound waves of moderate intensity in liquid encounter an air interface, a chain of drops emerges from the liquid surface to form what is known as a drop-chain fountain. Atomization, or the emission of micro-droplets, occurs when the acoustic intensity exceeds a liquid-dependent threshold. While the cavitation-wave hypothesis, which states that atomization arises from a combina...

Anhydrous liquid ammonia has a boiling point of -33.35 C, which might suggest that it would be a difficult material to handle, particularly in light of the familiar noxious odor of the gas. However, owing to hydrogen bonding, liquid ammonia has a relatively high heat of vaporization (23.3 J/mol vs. 40.7 J/mol for H2O). Thus, if kept in an insulated vessel (e.g., a Dewar flask), its rate of vapo...

Film boiling on a horizontal tube is used to study the thermal decomposition of ethyl acetate. The decomposition process is driven by the high surface temperatures that are typical of the film boiling regime that can promote chemical change of superheated vapors in a low temperature liquid. The decomposition products are carried away from the tube by vapor bubbles formed at the top of the tube ...

The migration characteristics of carbon nanotubes from liquid phase to vapor phase in the refrigerant-based nanofluid pool boiling were investigated experimentally. Four types of carbon nanotubes with the outside diameters from 15 to 80 nm and the lengths from 1.5 to 10 μm were used in the experiments. The refrigerants include R113, R141b and n-pentane. The oil concentration is from 0 to 10 wt....