The roles of the binodal curve and the spinodal curve in expansions from the supercritical state with flashing

The dynamics of the water outflow from the initial supercritical state through a thin nozzle is studied. To describe the initial stage of non-stationary process outflow the system of differential equations of conservation of mass, momentum and energy in a two-dimensional cylindrical coordinates with axial symmetry is used. The spatial distribution of pressure and velocity of jet formation was received. It was established that a supersonic regime of outflow at supercritical temperature of 650 K is formed, which have a qualitative agreement for the velocity compared with the Bernoulli analytical solution and the experimental data.

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A note on scenarios of metastable water

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc2009543 ◽

2010 ◽

Vol 75 (5) ◽

pp. 593-605 ◽

Cited By ~ 4

Author(s):

Jan Jirsák ◽

Ivo Nezbeda

Keyword(s):

Computer Simulations ◽

Equations Of State ◽

Stability Limit ◽

Spinodal Curve ◽

Spinodal Line ◽

Metastable Water

A recently developed molecular-based equations of state for water are analyzed with respect to the behavior of the liquid spinodal curve. It is shown that all of them yield the spinodal exhibiting a minimum in accordance with Speedy’s stability-limit conjecture and with the behavior predicted by the accurate (but purely empirical) IAPWS-95 equation. It means that the considered equations of state give consistent results but qualitatively different from those resulting from available computer simulations, which yield a monotonic spinodal line.

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Numerical Investigation of Natural Convection Heat Transfer in Porous Medium Saturated With Carbon Dioxide in Supercritical State

AL-Rafdain Engineering Journal (AREJ) ◽

10.33899/rengj.2012.47286 ◽

2012 ◽

Vol 20 (2) ◽

pp. 86-97

Author(s):

Dr. Amir S. Dawood ◽

Younis M. Najim ◽

Mohanad K. Radhi

Keyword(s):

Heat Transfer ◽

Carbon Dioxide ◽

Porous Medium ◽

Natural Convection ◽

Numerical Investigation ◽

Convection Heat Transfer ◽

Natural Convection Heat Transfer ◽

Supercritical State ◽

Convection Heat

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Влияние напряжения смещения и скорости осаждения на структуру и коэрцитивность пленок NiFe

Физика твердого тела ◽

10.21883/ftt.2020.12.50221.163 ◽

2020 ◽

Vol 62 (12) ◽

pp. 2174

Author(s):

А.С. Джумалиев ◽

C.Л. Высоцкий ◽

В.К. Сахаров

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Film Thickness ◽

Deposition Rate ◽

Entire Range ◽

Soft Magnetic Properties ◽

Supercritical State ◽

Dc Magnetron Sputtering ◽

Soft Magnetic ◽

Critical Film Thickness

Influence of the bias voltage Ub and the deposition rate  on the structure, grain size D, and coercivity Hc of NiFe films with the thickness d from 30 to 980 nm, grown onto Si / SiO2 substrates by DC magnetron sputtering, was studied. In the case Ub = 0, the decrease of  from ≈ nm/min to ≈ 7 nm/min is accompanied by the increase of the critical film thickness dcr from dcr ≈ 220 nm to dcr ≈ 270 nm. In this case, Hc in the films with d < dcr is characterized by the dependence Hc ~ D6 and varies from ~ 1 to ~ 20 Oe. In the case of Ub = -100 V, the effect of the deposition rate on the coercivity is much more noticeable. At ν = 7 and 14 nm / min, the films demonstrate soft magnetic properties (Нс ≈ 0.15 - 1.4 Oe) and the absence of dcr for the entire range of studied thicknesses. The films obtained at ν = 21 and 27 nm / min turn into the “supercritical” state at d ≥ dcr ≈ 520 nm, and, in the region d < dcr, they are characterized by the dependence Hc ~ D3 and by the increase of coercivity from ~ 0.35 to ~ 10 Oe.

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