The effects of dissolved air in the dielectric liquid FC-77 on flow boiling in a microchan-nel heat sink containing ten parallel channels, each 500 ␮m wide and 2.5 mm deep, were experimentally investigated. Experiments were conducted before and after degas-sing, at three flow rates in the range of 30– 50 ml/ min. The dissolved air resulted in a significant reduction in wall temperature at which...

Pool boiling experiments were conducted with three horizontal, flat, silicon surfaces, two of which were coated with vertically aligned multiwalled carbon nanotubes (MWCNTs). The two wafers were coated with MWCNT of two different thicknesses: 9 m (Type-A) and 25 m (Type-B). Experiments were conducted for the nucleate boiling and film boiling regimes for saturated and subcooled conditions with l...

When He gas is injected from room temperature into boiling liquid N2, boiling is suppressed, leaving liquid surface flat like a mirror. Although the qualitative explanation for this phenomenon is known [Minkoff G J et al. Nature 1957;180(4599):14134.], it has not been studied quantitatively and comprehensively yet. In this report, we made careful simultaneous measurements of temperature and wei...

Controlling boiling incipience is of paramount importance for reliable operation of liquid-cooled microelectronic heat sources during power transients. This study focuses on heat transfer from a simulated multichip module to a falling film. Experiments have been performed to develop an understanding of the influence of surface tension and wetting characteristics on sensible heat transfer and bo...

A newly simplified microstructure model of metal foams was carried out for flow boiling heat transfer in metal-foam filled tube. Fin analysis, heat transfer network and superposition correlation were adopted to obtain the equivalent heat transfer coefficient for flow boiling. Based on annular pattern, fluid can be divided into vapor region in the center of the tube and liquid region near the wa...

Demand for high-performance cooling systems is one of the most challenging and virtual issues in the industry and Pulsating heat pipes are effective solutions for this concern. In the present study, the best predictor correlations of flow boiling and condensation are taken into account to model a single turn pulsating heat pipe mathematically. These considerations, result in derivation of more ...

We describe a theoretical model of the fluid flow, heat transfer and phase change which occurs when liquid is injected into a fracture bounded by a hot, impermeable rock. We first consider the case of a warm host rock, in which there is no boiling of the water. We then develop the model to describe the case in which the host rock temperature is in excess of the boiling temperature and the water...

In this study, the use of the three-layer feed forward neural network has been investigated for estimating of infinite dilute diffusion coefficient ( D12 ) of supercritical fluid (SCF), liquid and gas binary systems. Infinite dilute diffusion coefficient was spotted as a function of critical temperature, critical pressure, critical volume, normal boiling point, molecular volume in normal boilin...

Vapor degreasing uses a partially full container of cleaner heated to its boiling point. The parts to be cleaned are suspended in the vapor cloud above the boiling liquid. The vapor condenses on the cooler parts, dissolves the contaminants and flushes the liquid mixture back into the hot liquid. When the cleaning process is complete, the parts are removed from the tank and they quickly dry in t...

The literature pertinent to various aspects of drop evaporation on a heated surface is reviewed. Both the laser shadowgraphic and direct photographic methods are employed to study thermal stability and flow structures in evaporating drops in all heating regimes. It is revealed that four flow regions exist in stable and unstable type drops at low liquid-film type vaporization regime. As the surf...