It’s believed that the macrolayer plays an important role in nucleate and transition boiling heat transfer at high heat flux. Many experiments have been carried out to support the macrolayer evaporation model, however, little has been conducted in the numerical simulation of boiling heat transfer. In this study, based on the macrolayer evaporation model of Maruyama et al. (1992), a numerical si...

There are many astringent date cultivars at maturity (Full coloration) around the world. These fruits could not be consumed at this stage due to the presence of soluble tannins. Growers have to wait until about 50% of these bunches reach to the rutab stage (ripening) which represents a major source of fruit loss due to abscission, birds attack and pathogens. Furthermore, late-maturing cultivars...

The current study investigates capillary-fed boiling of water from porous sintered powder wicks used in emerging high-effective-conductivity vapor chamber heat spreaders intended for management of hot spots with heat fluxes exceeding 500 W cm . Characterization of 1 mm thick wicks composed of 100 lm sintered copper particles is performed in a test facility which replicates the capillary feeding...

The current study investigates capillary-fed boiling of water from porous sintered powder wicks used in emerging high-effective-conductivity vapor chamber heat spreaders intended for management of hot spots with heat fluxes exceeding 500 W cm -2 . Characterization of 1 mm-thick wicks composed of 100 μm sintered copper particles is performed in a test facility which replicates the capillary feed...

A compact packaging module for direct liquid cooling of roomtemperature quantum cascade lasers is implemented. The light was coupled out of the hermetically sealed package through a mid-infrared fibre epoxy-bonded to the laser. The threshold current reduces by 10%, compared to convectional substrate-side cooled lasers when using low boiling temperature (boiling point (b.p.)1⁄4 34 C) 3M HFE7000 ...

– Boiling crisis is the rapid formation of the quasi-continuous vapor film between the heater and the liquid when the heat supply exceeds a critical value. We propose a mechanism for the boiling crisis that is based on the spreading of the dry spot under a vapor bubble. The spreading is initiated by the vapor recoil force, a force coming from the liquid evaporation into the bubble. Since the ev...

Pool boiling experiments were conducted in microgravity on five space shuttle flights, using a flat plate heater consisting of a semitransparent thin gold film deposited on a quartz substrate that also acted as a resistance thermometer. The test fluid was R-113, and the vapor bubble behavior at the heater surface was photographed from beneath as well as from the side. Each flight consisted of a...

The fractal nature of hydrodynamic features during nucleate boiling is illustrated in this study. Earlier reports in the literature explored the fractal nature of the thermal features in pool boiling. In these studies typically the time-delay technique was used to obtain chaos quantifiers in boiling from wall temperature fluctuation measurements. In this study experiments were performed at diff...

Dioxane and water form a positive homoazeotrope which has an azeotropic decrease in temperature sufficiently large to effect the complete r emoval, by fractional distillation through an efficient column, of water present as an impurity. The boiling-point-composition diagram, including the composition of the vapor in equilibrium with the boiling liquid, was determined. The normal boiling point o...