Cathode sputtering with electrical discharge through a heavy water-saturated vapor interface

A numerical model of the evaporating liquid meniscus under saturated vapor conditions in wick microstructures has been developed. Four different wick geometries representing the common wicks used in heat pipes, viz., wire mesh, rectangular grooves, sintered wicks and vertical microwires, are modeled and compared for evaporative performance. The solid-liquid combination considered is copper-water. Steady evaporation is modeled and the liquid-vapor interface shape is assumed to be static during evaporation. Liquid-vapor interface shapes in different geometries are obtained by solving the Young-Laplace equation using Surface Evolver. Mass, momentum and energy equations are solved numerically in the liquid domain, with the vapor assumed to be saturated. Evaporation at the interface is modeled by using appropriate heat and mass transfer rates obtained from kinetic theory. Thermo-capillary convection due to non-isothermal conditions at the interface is modeled for all geometries and its role in heat transfer enhancement from the interface is quantified for both low and high superheats. More than 80% of the evaporation heat transfer is noted to occur from the thin-film region of the liquid meniscus. Very small Capillary and Weber numbers arising due to small fluid velocities near the interface for low superheats validate the assumption of static liquid meniscus shape during evaporation. Solid-liquid contact angle, wick porosity, solid-vapor superheat and liquid level in the wick pore are varied to study their effects on evaporation from the liquid meniscus.

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Analysis of thermodynamic process of water vapor in boiler

E3S Web of Conferences ◽

10.1051/e3sconf/202125202043 ◽

2021 ◽

Vol 252 ◽

pp. 02043

Author(s):

Yarong Wang ◽

Peirong Wang

Keyword(s):

Water Vapor ◽

Saturated Vapor ◽

Engineering Application ◽

Generation Process ◽

Steam Power ◽

Saturated Water ◽

Working Medium ◽

Vapour Mixture ◽

Three Stages ◽

Water Saturated

In steam power plant, the working medium used for energy transformation is water vapor. The generation process of water vapor has experienced three stages: pre-heat, vaporization and superheat stage. There are five states in the process. They are sub-cooled liquid, saturated water, saturated liquid-vapour mixture, saturated vapor and superheated vapor. The thermodynamic properties of each state are usually obtained by using water vapor tables and charts. The constant pressure process of water vapor is very common in engineering application. In general, we first determine the state parameters by using charts and tables, and then make relevant calculations according to the first law of thermodynamics.

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Note on the Conversion of Stilbite and Heulandite into Wairakite under Very Low Water Saturated Vapor Pressure

Proceedings of the Japan Academy ◽

10.2183/pjab1945.42.925 ◽

1966 ◽

Vol 42 (8) ◽

pp. 925-928 ◽

Cited By ~ 2

Author(s):

Kazuo HARADA ◽

Katsutoshi TOMITA ◽

Toshio SUDO

Keyword(s):

Vapor Pressure ◽

Saturated Vapor Pressure ◽

Saturated Vapor ◽

Water Saturated

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Effects of Electrical Discharges in Low Pressure Gases on the Morphology of Polyethylene Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052730 ◽

1974 ◽

Vol 32 ◽

pp. 544-545

Author(s):

L.H. Bolz ◽

D.H. Reneker

Keyword(s):

Power Distribution ◽

Electrical Discharge ◽

Dielectric Breakdown ◽

Ionic Species ◽

Low Pressure ◽

Polymer Surfaces ◽

Electrical Discharges ◽

Adhesive Bonds ◽

Power Distribution Lines ◽

Modification Of The Surface

The attack, on the surface of a polymer, by the atomic, molecular and ionic species that are created in a low pressure electrical discharge in a gas is interesting because: 1) significant interior morphological features may be revealed, 2) dielectric breakdown of polymeric insulation on high voltage power distribution lines involves the attack on the polymer of such species created in a corona discharge, 3) adhesive bonds formed between polymer surfaces subjected to such SDecies are much stronger than bonds between untreated surfaces, 4) the chemical modification of the surface creates a reactive surface to which a thin layer of another polymer may be bonded by glow discharge polymerization.

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An Environmental Wet Cell For High Voltage Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070539 ◽

1973 ◽

Vol 31 ◽

pp. 18-19

Author(s):

N.J. Tighe ◽

H.M. Flower ◽

P.R. Swann

Keyword(s):

Electron Microscopy ◽

High Temperature ◽

Image Quality ◽

Inelastic Scattering ◽

High Voltage ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Environmental Cell ◽

Water Saturated ◽

High Temperature Gas

A differentially pumped environmental cell has been developed for use in the AEI EM7 million volt microscope. In the initial version the column of gas traversed by the beam was 5.5mm. This permited inclusion of a tilting hot stage in the cell for investigating high temperature gas-specimen reactions. In order to examine specimens in the wet state it was found that a pressure of approximately 400 torr of water saturated helium was needed around the specimen to prevent dehydration. Inelastic scattering by the water resulted in a sharp loss of image quality. Therefore a modified cell with an ‘airgap’ of only 1.5mm has been constructed. The shorter electron path through the gas permits examination of specimens at the necessary pressure of moist helium; the specimen can still be tilted about the side entry rod axis by ±7°C to obtain stereopairs.

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Scanning electron microscopy of plant cells using a variable-pressure SEM and cryogenic techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147144 ◽

1993 ◽

Vol 51 ◽

pp. 260-261

Author(s):

M. Yamada ◽

K. Ueda ◽

K. Kuboki ◽

H. Matsushima ◽

S. Joens

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Saturated Vapor ◽

Plant Cells ◽

Variable Pressure ◽

Specimen Preparation ◽

Operating Pressure ◽

Vapor Pressures ◽

Low Temperature Microscopy ◽

Scanning Electron

Use of variable Pressure SEMs is spreading among electron microscopists The variable Pressure SEM does not necessarily require specimen Preparation such as fixation, dehydration, coating, etc which have been required for conventional scanning electron microscopy. The variable Pressure SEM allows operating Pressure of 1˜270 Pa in specimen chamber It does not allow microscopy of water-containing specimens under a saturated vapor Pressure of water. Therefore, it may cause shrink or deformation of water-containing soft specimens such as plant cells due to evaporation of water. A solution to this Problem is to lower the specimen temperature and maintain saturated vapor Pressures of water at low as shown in Fig. 1 On this technique, there is a Published report of experiment to have sufficient signal to noise ratio for scondary electron imaging at a relatively long working distance using an environmental SEM. We report here a new low temperature microscopy of soft Plant cells using a variable Pressure SEM (Hitachi S-225ON).

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