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...

jet impingement boiling is investigated with regard to heat transfer and pressure drop performance using a novel laser sintered 3D printed jet impingement manifold design. Water was the working fluid at atmospheric pressure with inlet subcooling of 7 o C. The convective boiling performance of the impinging jet system was investigated for a flat copper target surface for 2700≤Re≤5400. The result...

This chapter provides the engineer and the researcher with correlations and models for the prediction of the critical aspects of the boiling heat transfer of mixtures. This chapter offers a reliable, hands-on resource for solving common problems across pool boiling and flow boiling applications such as miscible mixtures, refrigerant/lubricant mixtures, additives, and refrigerant/nanolubricants....

Mixtures of ethylene glycol and water are used in cooling the engines in automotive applications. To avoid the two-phase flow in the engine, the mixture is subcooled in the radiator before entering the engine block. Heat transfer is therefore essentially under subcooled flow boiling conditions. Very little information is available in the literature on the subcooled flow boiling characteristics ...

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...

As is well known, boiling is an effective mode of heat transfer in that high heat flux levels are possible with relatively small temperature differences. Its optimal application requires that the process be adequately understood. A measure of the understanding of any physical event lies in the ability to predict its behavior in terms of the relevant paramem. Despite many years of research the p...

Boiling is a very efficient way to transfer heat from a heater to the liquid carrier. We discuss the boiling crisis, a transition between two regimes of boiling: nucleate and film boiling. The boiling crisis results in a sharp decrease in the heat transfer rate, which can cause a major accident in industrial heat exchangers. In this communication, we present a physical model of the boiling cris...

Flow boiling in microchannels has received considerable attention from researchers worldwide in the last decade. A scaling analysis is presented to identify the relative effects of different forces on the boiling process at microscale. Based on this scaling analysis, the flow pattern transitions and stability for flow boiling of water and FC-77 are evaluated. From the insight gained through the...

Transient nucleate pool boiling experiments using R113 are conducted for short times in microgravity and in earth gravity with different heater surface orientations and subcoolings. The heating surface is a transparent gold film sputtered on a quartz substrate, which simultaneously provides surface temperature measurements and permits viewing of the boiling process from beneath. For the microgr...

The heat of vaporization of a pure substance at its normal boiling temperature is a very important property in many chemical processes. In this work, a new empirical method was developed to predict vaporization enthalpy of pure substances. This equation is a function of normal boiling temperature, critical temperature, and critical pressure. The presented model is simple to use and provides an ...