Conduction and single-phase convective heat transfer are well understood phenomena: analytical models [1] and empirical correlations [2] allow capturing the thermal behavior of plate-type fuels or heaters in contact with a single-phase coolant. On the other hand, transient boiling heat transfer is a scarcely studied and much less understood phenomenon. Although, earlier studies have shown that ...

Atomization and fountain formation is a well-known phenomenon that occurs when a focused ultrasound wave in liquid encounters an air interface. High intensity focused ultrasound (HIFU) has been shown to fractionate a tissue into submicron-sized fragments in a process termed boiling histotripsy, wherein the focused ultrasound wave superheats the tissue at the focus, producing a millimetre-sized ...

Published studies concerning transport phenomena in micro-channel heat sinks can be divided into those concerning saturated boiling versus those focused on subcooled boiling, with the vast majority related to the former. What has been lacking is a single generalized method to tackle both boiling regimes. The primary objective of the present paper is to construct a consolidated method to predict...

In this paper the heat transfer characteristics of a two-phase closed thermosyphon over a wide range of heat transfer rates, system pressure, aspect ratios and filling ratios were studied. The experiments focused on the boiling and condensation heat transfer characteristics of the thermosyphon. The experimental boiling and condensation heat transfer coefficients inside the thermosyphon were com...

This work examines the e}ectiveness of the zero!angle cavities created by curved contact with a ~at surface in promoting vapor embryo capture\ low temperature boiling incipience\ and reduction or elimination of the incipience temperature overshoot with highly wetting liquids[ Using FC!61 as a test liquid\ both single and multiple spherical point contacts on a ~at heater in both horizontal and v...

Droplets impacting on a superheated surface can either exhibit a contact boiling regime, in which they make direct contact with the surface and boil violently, or a film boiling regime, in which they remain separated from the surface by their own vapor. The transition from the contact to the film boiling regime depends not only on the temperature of the surface and the kinetic energy of the dro...

This paper deals with the application of steam to enhance the recovery from petroleum reservoirs. We formulate a mathematical and numerical model that simulates coinjection of volatile oil with steam into a porous rock in a one-dimensional setting. We utilize the mathematical theory of conservation laws to validate the numerical simulations. This combined numerical and analytical approach revea...

Micro scale boiling behavior in the vicinity of graphite micro-fiber tips on the coppergraphite composite boiling surfaces is investigated. It is discovered that a large number of micro bubbles are formed first at the micro scratches and cavities on the copper matrix in pool boiling. In virtue of the non-wetting property of graphite, once the growing micro bubbles touch the graphite tips, the m...

Mixtures of ethylene glycol and water are used in cooling the engines in automotive applications. Heat is transferred essentially under subcooled flow boiling conditions as the mixture flows over the hot surfaces, which are at temperatures well above the local saturation temperature of the mixture. Very little information is available in the literature on the subcooled flow boiling characterist...