Due to the dependence of boiling heat transfer rate on heat flux, saturation pressure, mass flux and refrigerant quality, efforts made to increase heat transfer rate often cause further drop in refrigerant saturation pressure. In this study, entropy generation mechanisms associated with two-phase flow in smooth evaporator tube subject to constant surface heat flux are investigated. Refrigerant ...

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...

The local two-phase heat transfer coefficient is a critical parameter in the design of microchannel cold plate evaporators used in applications such as electronics cooling systems. Only a few past studies on microchannels have investigated the heat transfer characteristics over the entire vapor quality range and conflicting trends have been reported even in these studies. Therefore, the present...

The ˆrst section of this paper (overview on boiling heat transfer characteristics) is directed to those who are not specialists in the ˆeld of boiling heat transfer, in order to make them aware of the fundamental physical mechanisms, the advantages and the main problems of this technique. Next, some of the basic knowledge achieved on terrestrial boiling heat transfer is outlined, along with the...

A novel microfabrication technique was developed to create silicon nanowires (SiNWs) on orthogonal surfaces of microchannels machined on top of a silicon wafer. Using a two-step metal-assisted etching process, the SiNW for the first time could be selectively fabricated on two different crystalline directions—the channel top and bottom surfaces oriented in the (1 0 0) direction while the sidewal...

The present study is performed to numerically analyze an evaporating meniscus bounded between the advancing and receding interfaces on a moving heated surface. The numerical scheme developed for analyzing interface motion during bubble growth in pool boiling has been applied. A column of liquid is placed between a nozzle outlet and a moving wall, and calculations are done in two dimensions with...

Two-phase heat transfer in microchannels can support very high heat fluxes for use in high-performance electronics-cooling applications. However, the effects of microchannel crosssectional dimensions on the heat transfer coefficient and pressure drop have not been investigated extensively. In the present work, experiments are conducted to investigate the local flow boiling heat transfer in micr...