The purpose of this paper is to report the results of a new model study examining the high temperature nuclear waste disposal concept at Yucca Mountain using MULTIFLUX, an integrated indriftand mountain-scale thermal-hydrologic model. The results show that a large amount of vapor flow into the drift is expected during the period of above-boiling temperatures. This phenomenon makes the emplaceme...

Paolo Di Marco Walter Grassi Dipartimento di Energetica, Universit?~ di Pisa, Pisa, Italy • The purpose of the paper is to experimentally assess the effect exerted by subcooling degree and heat-up rate (i.e., the rate of increase of thermal flux) on the phenomenon of nucleate boiling in the presence of an electric field. To this aim, an experimental facility was set up to investigate pool boili...

Nucleate pool boiling heat transfer coefficient have been experimentally measured on a horizontal rod heater for various liquid binary mixtures. Measurements are based on more than three hundred data points on a wide range of concentrations and heat fluxes. In this investigation, it has been confirmed that the heat transfer coefficient in boiling solutions are regularly less than those in p...

– 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...

nucleate pool boiling heat transfer coefficient have been experimentally measured on a horizontal rod heater for various liquid binary mixtures. measurements are based on more than three hundred data points on a wide range of concentrations and heat fluxes. in this investigation, it has been confirmed that the heat transfer coefficient in boiling solutions are regularly less than those in pure ...

Critical Heat Flux (CHF) has been a subject of interest for boiling equipment designers from design as well safety as viewpoints. Although considerable data exists in literature, a fundamental knowledge of the mechanisms responsible for the CHF phenomenon is needed to develop better predictive methods and efficient enhancement strategies. A critical assessment of the CHF models available in the...

Enhancing the critical heat flux (CHF) of industrial boilers by surface texturing can lead to substantial energy savings and global reduction in greenhouse gas emissions, but fundamentally this phenomenon is not well understood. Prior studies on boiling crisis indicate that CHF monotonically increases with increasing texture density. Here we report on the existence of maxima in CHF enhancement ...

Tubes with boiling are common elements of many processes. They appear in steam generators and refrigerators and many other systems. The behavior of such systems is complicated and many physical phenomena are involved. It has for example been observed that different types of instabilities can occur. In this paper we will discuss modeling of tubes with boiling. As an application we will discuss a...

To study energy recovery from low temperature wastewater during industrial production, a water-boiling heat transfer experimental device was built. A casing evaporator with length of 1450 mm, an inner tube diameter 30 and annular space gap 14.2 mm is taken as the main research object. The boiling characteristics water in area were experimentally studied by adjusting inlet (60? 85?C) hot pressur...