Interfacial Area Transport of Vertical Upward Annular Two-Phase Flow

Accurate prediction of the interfacial area concentration is essential to successful development of the interfacial transfer terms in the two-fluid model. The interfacial area concentration in annular flow and annular mist flow is especially relevant to the transition process to the liquid film dryout, which might lead to fatal problem in the safety and efficient operation of boiling heat transfer system. However, very few experimental and theoretical studies focusing on the interfacial area concentration in annular flow region have been conducted. From this point of view, accurate measurements of annular flow parameters such as local liquid film thickness, one-dimensional interfacial area concentration of liquid film, and local interfacial area concentration profile of liquid film were performed by a laser focus displacement meter at 21 axial locations in vertical upward annular two-phase flow using a 3-m-long and 11-mm-diameter pipe. The axial distances from the inlet (z) normalized by the pipe diameter (D) varied over z/D = 50 to 250. Data were collected for preset gas and liquid flow conditions and for Reynolds numbers ranging from Reg = 31,800 to 98,300 for the gas phase and Ref = 1,050 to 9,430 for the liquid phase. Axial development of the one-dimensional interfacial area concentration and the local interfacial area concentration profile of liquid film were examined with the data obtained in the experiment. Total interfacial area concentration including liquid film and droplets was also discussed with help of the existing drift-flux model, entrainment correlation, and droplet size correlation.

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Axial Development of Vertical Upward Bubbly Flow in a Minipipe

Heat Transfer: Volume 2 ◽

10.1115/ht2005-72413 ◽

2005 ◽

Cited By ~ 4

Author(s):

Tatsuya Hazuku ◽

Naohisa Tamura ◽

Norihiro Fukamachi ◽

Tomoji Takamasa ◽

Takashi Hibiki ◽

...

Keyword(s):

Void Fraction ◽

Two Phase Flow ◽

Constitutive Relations ◽

Interfacial Area ◽

Phase Flow ◽

Two Phase ◽

Flow Measurements ◽

Local Flow ◽

Interfacial Area Concentration ◽

Drift Flux Model

Accurate prediction of the interfacial area concentration is essential to successful development of the interfacial transfer terms in the two-fluid model. Mechanistic modeling of the interfacial area concentration entirely relies on accurate local flow measurements over extensive flow conditions and channel geometries. From this point of view, accurate measurements of flow parameters such as void fraction, interfacial area concentration, gas velocity, bubble Sauter mean diameter, and bubble number density were performed by the image processing method at five axial locations in vertical upward bubbly flows using a 1.02 mm-diameter pipe. The frictional pressure loss was also measured by a differential pressure cell. In the experiment, the superficial liquid velocity and the void fraction ranged from 1.02 m/s to 4.89 m/s and from 0.980% to 24.6%, respectively. The obtained data give near complete information on the time-averaged local hydrodynamic parameters of two-phase flow. These data can be used for the development of reliable constitutive relations which reflect the true transfer mechanisms in two-phase flow. As the first step to understand the flow characteristics in mini-channels, the applicability of the existing drift-flux model, interfacial area correlation, and frictional pressure correlation was examined by the data obtained in the mini-channel.

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Axial Development of Interfacial Area Concentration of Liquid Film in Vertical Upward Annular Two-phase Flow

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.72.1189 ◽

2006 ◽

Vol 72 (717) ◽

pp. 1189-1196

Author(s):

Tatsuya HAZUKU ◽

Takashi HIBIKI ◽

Tomoji TAKAMASA ◽

Mamoru ISHII

Keyword(s):

Liquid Film ◽

Two Phase Flow ◽

Interfacial Area ◽

Phase Flow ◽

Two Phase ◽

Interfacial Area Concentration ◽

Axial Development

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Local and Area-Averaged Flow Structure of Air-Water Two-Phase Flow in a Vertical Annulus

Volume 3: Thermal Hydraulics; Instrumentation and Controls ◽

10.1115/icone16-48067 ◽

2008 ◽

Cited By ~ 1

Author(s):

Basar Ozar ◽

Jae Jun Jeong ◽

Abhinav Dixit ◽

Jose Enrique Julia´ ◽

Takashi Hibiki ◽

...

Keyword(s):

Flow Structure ◽

Test Section ◽

Two Phase Flow ◽

Interfacial Area ◽

Phase Flow ◽

Flow Conditions ◽

Two Phase ◽

Interfacial Area Concentration ◽

Drift Flux Model ◽

Vertical Annulus

The flow structure of gas-liquid two-phase flow has been investigated in a vertical annulus channel. The annulus consisted of a geometry where the inner diameter was 19.1 mm and the outer diameter was 38.1 mm. The total height of the test section was 4.37 m. Experiments were conducted for nineteen inlet flow conditions. These flow conditions covered bubbly, cap-slug, and churn-turbulent flows. The local flow parameters, such as void fraction, interfacial area concentration, and bubble interface velocity, were measured at nine radial positions within the gap of the annulus at z/Dh = 230 of the test section. Radial distributions of these parameters were interpreted in terms of turbulent velocity profile, lift and wall forces. In addition, the local measurements were used to calculate distribution parameter, C0 in drift-flux model, and area averaged interfacial area concentration. Ishii’s (1977) model was modified and a new correlation of C0 was proposed based on the experimentally obtained C0 values. The area-averaged interfacial area concentration (IAC) values were compared with the most widely used models (Ishii and Mishima, 1980; Spore et al., 1983; Hibiki and Ishii, 2002). The advantages and drawbacks of these models were highlighted.

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Code performance with improved two-group interfacial area concentration correlation for one-dimensional forced convective two-phase flow simulation

Journal of Nuclear Science and Technology ◽

10.1080/00223131.2018.1449680 ◽

2018 ◽

Vol 55 (8) ◽

pp. 911-930 ◽

Cited By ~ 1

Author(s):

Tetsuhiro Ozaki ◽

Takashi Hibiki ◽

Shuichiro Miwa ◽

Michitsugu Mori

Keyword(s):

Two Phase Flow ◽

Flow Simulation ◽

Interfacial Area ◽

Phase Flow ◽

Two Phase ◽

Interfacial Area Concentration ◽

One Dimensional ◽

Code Performance

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Axial Development of Gas-Liquid Two-Phase Flow in Mini-Channels

Volume 4: Computational Fluid Dynamics, Neutronics Methods and Coupled Codes; Student Paper Competition ◽

10.1115/icone14-89612 ◽

2006 ◽

Author(s):

Junichi Uematsu ◽

Yoshinori Hirose ◽

Tatsuya Hazuku ◽

Tomoji Takamasa ◽

Takashi Hibiki

Keyword(s):

Void Fraction ◽

Two Phase Flow ◽

Interfacial Area ◽

Phase Flow ◽

Two Phase ◽

Flow Measurements ◽

Local Flow ◽

Interfacial Area Concentration ◽

Drift Flux Model ◽

Mini Channels

Accurate prediction of the interfacial area concentration is essential to successful development of the interfacial transfer terms in the two-fluid model. Mechanistic modeling of the interfacial area concentration entirely relies on accurate local flow measurements over extensive flow conditions and channel geometries. From this point of view, accurate measurements of flow parameters such as void fraction, interfacial area concentration, gas velocity, bubble Sauter mean diameter, and bubble number density were performed by the image processing method at five axial locations in vertical upward bubbly flows using 1.02 and 0.55 mm-diameter pipes. The frictional pressure loss was also measured by a differential pressure cell. In the experiment, the superficial liquid velocity and the void fraction ranged from 0.475 m/s to 4.89 m/s and from 0.980% to 28.6%, respectively. The obtained data give near complete information on the time-averaged local hydrodynamic parameters of two-phase flow. These data can be used for the development of reliable constitutive relations which reflect the true transfer mechanisms in two-phase flow. As the first step to understand the flow characteristics in mini-channels, the applicability of the existing drift-flux model, interfacial area correlation, and frictional pressure correlation was examined by the data obtained in the mini-channels.

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A Physically Based, One-Dimensional Two-Fluid Model for Direct Contact Condensation of Steam Jets Submerged in Subcooled Water

Journal of Nuclear Engineering and Radiation Science ◽

10.1115/1.4029417 ◽

2015 ◽

Vol 1 (2) ◽

Cited By ~ 6

Author(s):

David Heinze ◽

Thomas Schulenberg ◽

Lars Behnke

Keyword(s):

Direct Contact ◽

Two Phase Flow ◽

Fluid Model ◽

Interfacial Area ◽

Phase Flow ◽

Two Phase ◽

One Dimensional ◽

Two Fluid Model ◽

Contact Condensation ◽

Two Fluid

A simulation model for the direct contact condensation of steam in subcooled water is presented that allows determination of major parameters of the process, such as the jet penetration length. Entrainment of water by the steam jet is modeled based on the Kelvin–Helmholtz and Rayleigh–Taylor instability theories. Primary atomization due to acceleration of interfacial waves and secondary atomization due to aerodynamic forces account for the initial size of entrained droplets. The resulting steam-water two-phase flow is simulated based on a one-dimensional two-fluid model. An interfacial area transport equation is used to track changes of the interfacial area density due to droplet entrainment and steam condensation. Interfacial heat and mass transfer rates during condensation are calculated using the two-resistance model. The resulting two-phase flow equations constitute a system of ordinary differential equations, which is solved by means of the explicit Runge–Kutta–Fehlberg algorithm. The simulation results are in good qualitative agreement with published experimental data over a wide range of pool temperatures and mass flow rates.

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