Comparison of Profiles and Fluxes of Heat and Momentum Above and Below an Air-Water Interface

1982 ◽  
Vol 104 (1) ◽  
pp. 34-39 ◽  
Author(s):  
B. M. Howe ◽  
A. J. Chambers ◽  
S. P. Klotz ◽  
T. K. Cheung ◽  
R. L. Street
Keyword(s):  
Heat Transfer ◽  
Surface Layer ◽  
Water Surface ◽  
Temperature Fields ◽  
Water Interface ◽  
Law Of The Wall ◽  
Air Water Interface ◽  
Total Energy Flux ◽  
Momentum And Heat Transfer ◽  
Water Surface Layer

The velocity and temperature fields on both sides of an air-water interface were examined experimentally in order to understand better the physical processes of momentum and heat transfer through the surface layers about the interface. An examination of temperature and velocity profiles plotted in “law-of-the-wall” coordinates leads to the conclusion that, both in the air and in the water, the mechanism of momentum transfer is affected by surface roughness changes, but the mechanism of heat transfer is not. In the water surface layer the velocity fluctuations due to the wave-related motions are of the same order as the purely turbulent motions. The turbulent components closely resemble those found in boundary layers over solid walls. The measured total energy flux from the interface agrees well with the measured single-phase, vertical heat transport through the water surface layer.

Adsorption Kinetics of Nonanol at the Air−Water Interface:  Considering Molecular Interaction or Aggregation within Surface Layer

Langmuir ◽  
2002 ◽  
Vol 18 (7) ◽  
pp. 2686-2692 ◽  
Author(s):  
Ya-Chi Lee ◽  
Yu-Bing Liou ◽  
Reinhard Miller ◽  
Hwai-Shen Liu ◽  
Shi-Yow Lin
Keyword(s):  
Surface Layer ◽  
Adsorption Kinetics ◽  
Molecular Interaction ◽  
Water Interface ◽  
Air Water Interface ◽  
Kinetics Of

Surface Temperature Field Statistics at an Air/Water Interface for Grid-Generated Sub-Surface Turbulence

2002 ◽  
Author(s):  
Karen A. Flack ◽  
Geoffrey B. Smith
Keyword(s):  
Surface Temperature ◽  
Infrared Camera ◽  
Temperature Fields ◽  
Interface Temperature ◽  
Water Interface ◽  
Bulk Fluid ◽  
Air Water Interface ◽  
Evaporative Convection ◽  
The Difference ◽  
Oscillation Frequencies

Surface temperature fields and statistics are presented for the case of sub-surface grid-generated turbulence impacting an air/water interface. Temperature measurements are obtained with an infrared camera, sensitive in the 3–5 micron wavelength range. Results indicate that increased grid oscillation frequencies, and shallower grid depths, lead to increased surface mixing, yielding lower values of RMS temperature. Non-dimensionalization of the RMS temperatures using the difference in the average surface and the bulk fluid temperatures, collapses the data obtained for different grid depths and oscillation frequencies. This scaling is related to the thermal boundary layer thickness. The results are compared to the baseline case of turbulence due to evaporative convection without an oscillating grid.

Unified Molecular View of the Air/Water Interface Based on Experimental and Theoretical χ(2)Spectra of an Isotopically Diluted Water Surface

2011 ◽  
Vol 133 (42) ◽  
pp. 16875-16880 ◽  
Author(s):  
Satoshi Nihonyanagi ◽  
Tatsuya Ishiyama ◽  
Touk-kwan Lee ◽  
Shoichi Yamaguchi ◽  
Mischa Bonn ◽  
...  
Keyword(s):  
Water Surface ◽  
Water Interface ◽  
Air Water Interface

Calcite lilypads and ledges at Lorusio Hot Springs, Kenya Rift Valley: travertine precipitation at the air-water interface

1999 ◽  
Vol 36 (4) ◽  
pp. 649-666 ◽  
Author(s):  
Robin W Renaut ◽  
Brian Jones ◽  
Caroline Le Turdu
Keyword(s):  
Water Surface ◽  
Microbial Mats ◽  
Hot Springs ◽  
Water Interface ◽  
Kenya Rift ◽  
Similar Morphology ◽  
Northern Kenya ◽  
Air Water Interface ◽  
Capillary Evaporation ◽  
Outflow Channel

Travertine forming at Lorusio Hot Springs in the northern Kenya Rift is constructed mainly by lilypads and ledges. The lilypads are flat, accretionary structures rooted to the substrate that are composed mostly of platy calcite crystals. They grow outward from a nucleus, subparallel to the water surface, at or just below the air-water interface. Precipitation results from rapid degassing of CO2. Ledges, which have a similar morphology and internal structure, are attached to the margin of a spring pool or outflow channel. As they grow laterally, lilypads and ledges may coalesce with their neighbours to produce thin (1-3 cm) beds of travertine, examples of which are exposed in subfossil deposits at the site. Once established, lilypads and ledges modify the outflow and can act as substrates for precipitation of other minerals and colonization by microbes on their cooler subaerial surfaces. Pore fluids are drawn upward through the lilypads by capillary evaporation. Amorphous silica then precipitates as surficial crusts upon microbial mats or forms spicular microstromatolites, some of which also contain calcite laminae. Efflorescent Na-CO3 salts commonly encrust the drier central platforms of the exposed lilypad. The unusual abundance of lilypads and ledges at Lorusio reflects (i) the low-relief setting and the hydrostatic head, which limit terrace development, and (ii) the high temperature (>75°C) of the waters, which inhibits colonization by microbial mats at crystal growth sites. Similar structures form in cave pools, evaporating brines, and freezing water at sites where precipitation is induced by several processes active at the air-water interface.

scholarly journals Experimental Validation of RELAP5 and TRACE5 for Licensing Studies of the Boron Injection System of Atucha II

2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
Alejandro I. Lazarte ◽  
William Fullmer ◽  
Martín Bertodano
Keyword(s):  
Heat Transfer ◽  
Nuclear Power ◽  
Experimental Validation ◽  
Injection System ◽  
Water Interface ◽  
Experimental Facility ◽  
Pressure Losses ◽  
Air Water Interface ◽  
Loss Of Coolant ◽  
Tank Level

This paper presents an experimental validation of RELAP5 and TRACE5 for licensing studies of the Atucha II-PHWR nuclear power plant. A scaled experimental facility, representing the boron injection system of Atucha II, was built. The system has a fundamental importance for loss of coolant accidents (LOCA) and anticipated transients without scram (ATWS). The experiment consists of the discharge of a tank that represents the boron tank filled with air or a mixture of air-water onto a discharge tank that represents the moderator tank. Both tanks are connected by a pipe which includes a valve and an orifice plate to model the pressure losses due to the fittings in the real system. The pressure and water level measured in the tanks are compared with the RELAP5 and TRACE5 predictions. The codes predict the pressure in the tanks accurately. However, both codes overpredict the heat transfer in the boron tank air-water interface which produces a greater expansion of the air which leads to a small discrepancy in the boron tank level prediction.

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