2D Velocity Vector Profile Measurement and Phase Separation on Swirling Bubbly Flow Using Ultrasound Technique

Abstract Two-phase swirling bubbly flow is a complex phenomenon which occurs in several industries such as a nuclear reactor. Its characteristic is indispensably necessary to be investigated especially the multi-dimensional velocity distribution. This present paper describes the development of Ultrasonic Velocity Profiler (UVP) method which is a noninvasive measurement and needless of optical access, to obtain a two dimensional (2D) velocity distribution of the bubble and liquid phase in swirling bubbly flow simultaneously. The measurement result is represented in the form of the 2D velocity vector. To achieve the target, the multiple transducers and developed signal processing have been applied to the UVP system to measure a 2D velocity vector affected by bubble and liquid separately. For confirming the ability of Developed-UVP, the experiment was conducted on a vertical pipe co-current flow apparatus. The UVP measurement was demonstrated non-intrusively and without the optical requirement. The measurement applicability of Developed-UVP was evaluated by comparing with Particle Image Velocimetry (PIV) method on liquid flow and bubbly flow. Then, it was applied to obtain the 2D velocity vector in swirling bubbly flow. The velocity vector of the bubble and liquid could be separated clearly. Also, velocity distribution in swirling motion which was interacted of both phases was investigated understandably by using this measurement technique.

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Ultrasonic Measurement for the Experimental Investigation of Velocity Distribution in Vapor-Liquid Boiling Bubbly Flow

International Journal of Engineering and Technology Innovation ◽

10.46604/ijeti.2021.8329 ◽

2021 ◽

Vol 12 (1) ◽

pp. 16-28

Author(s):

Wongsakorn Wongsaroj ◽

Hideharu Takahashi ◽

Natee Thong-Un ◽

Hiroshige Kikura

Keyword(s):

Velocity Distribution ◽

Pipe Flow ◽

Pipe Wall ◽

Bubbly Flow ◽

Ultrasonic Measurement ◽

Subcooled Boiling ◽

Vertical Pipe ◽

Two Phase ◽

Flow Apparatus ◽

Vapor Liquid

This study proposes an ultrasonic velocity profiler (UVP) with a single ultrasonic gas-liquid two-phase separation (SUTS) technique to measure the velocity distribution of vapor-liquid boiling bubbly flow. The proposed technique is capable of measuring the velocity of the vapor bubble and liquid separately in boiling conditions. To confirm the viability of the measurement technique, the experiment is conducted on vertical pipe flow apparatus. The ultrasonic transmission and effect of ultrasonic refraction through the pipe wall and water are investigated at ambient temperature until subcooled boiling temperature is reached. The velocity profile in the water at elevated temperature is measured to verify the ability of the technique in this application. The bubbly flow velocity distribution measurement in boiling conditions is then demonstrated. The results show that the proposed technique can effectively investigate the velocity of both phases under various fluid conditions in boiling bubbly flow.

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Ultrasonic Measurement of Velocity Profile on Bubbly Flow Using a Single Resonant Frequency

Proceedings ◽

10.3390/icem18-05445 ◽

2018 ◽

Vol 2 (8) ◽

pp. 549 ◽

Cited By ~ 1

Author(s):

Wongsakorn Wongsaroj ◽

Ari Hamdani ◽

Natee Thong-un ◽

Hideharu Takahashi ◽

Hiroshige Kikura

Keyword(s):

Velocity Profile ◽

Resonant Frequency ◽

Bubble Column ◽

Bubbly Flow ◽

Frequency Component ◽

Instantaneous Velocity ◽

Two Phase ◽

Image Velocimetry ◽

Nonintrusive Measurement ◽

Flow Apparatus

The present paper describes a measurement technique for phase-separated velocity profile measurements in the two-phase bubbly flow. The Ultrasonic Velocity Profiler (UVP) method which is nonintrusive measurement, is applied to obtain an instantaneous velocity profile of liquid and bubble separately by using only one resonant frequency. To achieve this target, developed algorithm, which can decompose frequency component of the Doppler signal affected by liquid and bubble, is applied in the UVP system to obtain and separate instantaneous velocity profile of both phases. For confirming the applicability of modified measurement system, the developed UVP was used for the measurement of the velocity profile in bubbly flow on vertical pipe flow apparatus, the measurement accuracy was validated by UVP Original and Particle Image Velocimetry (PIV) method. Finally, the UVP was applied to experiment for observing velocity distribution of both phases in a bubble column.

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Analysis of Two-Phase Air/Water Bubbly Flow Experiment

Energy Conversion ◽

10.1115/imece2002-39689 ◽

2002 ◽

Author(s):

Donald R. Todd ◽

Yassin A. Hassan ◽

Javier Ortiz-Villafuerte

Keyword(s):

Particle Image ◽

Bubbly Flow ◽

Continuous Phase ◽

Three Dimensions ◽

Dispersed Phase ◽

Two Dimensional ◽

Two Phase ◽

Image Velocimetry ◽

Flow Experiment ◽

Shadow Image Velocimetry

Two different techniques, the Particle Image Velocimetry (PIV) and the Shadow-Image Velocimetry (SIV) techniques have been used to capture detailed two-phase bubbly flow experimental data. The PIV has provided a two-dimensional velocity field of the liquid phase for analysis of the continuous phase. The SIV has utilized to reconstruct the bubble shape and velocity of the dispersed phase in three-dimensions.

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Development of Prediction Technology of Two-Phase Flow Dynamics Under Earthquake Acceleration: (13) Rising Bubble Motion Under Horizontal Vibration

Volume 2A: Thermal Hydraulics ◽

10.1115/icone22-30009 ◽

2014 ◽

Cited By ~ 1

Author(s):

Rie Arai ◽

Akiko Kaneko ◽

Hideaki Monji ◽

Yutaka Abe ◽

Hiroyuki Yoshida ◽

...

Keyword(s):

Void Fraction ◽

Nuclear Reactor ◽

Two Phase Flow ◽

Liquid Velocity ◽

Nuclear Reactors ◽

Bubbly Flow ◽

Structural Safety ◽

Phase Flow ◽

Two Phase ◽

Safety Operation

An earthquake is one of the most serious phenomena for the safety of a nuclear reactor in Japan. Therefore, structural safety of nuclear reactors has been studied and nuclear reactors ware contracted with structural safety for a big earthquake. However, it is not enough for safety operation of nuclear reactors because thermal-fluid safety is not confirmed under the earthquake. For instance, behavior of gas-liquid two-phase flow is unknown under the earthquake conditions. Especially, fluctuation of void fraction is an important factor for the safety operation of the nuclear reactor. In the previous work, fluctuation of void faction in bubbly flow was studied experimentally and theoretically, to investigate the stability of the bubbly flow. In such studies, flow rate or void fraction fluctuations were given to the steady bubbly flow. In the case of the earthquake, the fluctuation is not only the flow rate, but also a body force on the two-phase flow and a shear force through a pipe wall. Interactions of gas and liquid through their interface also act on the behavior of the two-phase flow. The fluctuation of the void fraction is not clear for such complicated situation under the earthquake. Therefore, in this research project, the behavior of gas-liquid two-phase flow is investigated experimentally and numerically in the series of study. In this study, to investigate the effects of vibration on bubbly flow in the components and construct an experimental database for validation, we performed visualization experiments of vertical bubbly flow in a rectangular water tank on which a sine wave vibration was applied. In this paper, results of visualized experiment evaluated by the visualization techniques, including positions of bubbles, shapes of bubbles and liquid velocity distributions around bubbles, were shown. And liquid velocity distribution around bubbles by the PIV measurement was also shown. In the results, bubble behaviors were affected by oscillation. And the cycle of the bubble tilt angle was almost same as the cycle of oscillation table velocity.

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On the liquid turbulence energy spectra in two-phase bubbly flow in a large diameter vertical pipe

International Journal of Multiphase Flow ◽

10.1016/j.ijmultiphaseflow.2006.09.002 ◽

2007 ◽

Vol 33 (3) ◽

pp. 300-316 ◽

Cited By ~ 27

Author(s):

M.E. Shawkat ◽

C.Y. Ching ◽

M. Shoukri

Keyword(s):

Bubbly Flow ◽

Large Diameter ◽

Energy Spectra ◽

Turbulence Energy ◽

Vertical Pipe ◽

Two Phase

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KARAKTERISITIK FLOW PATERN PADA ALIRAN DUA FASE GAS-CAIRAN MELEWATI PIPA VERTIKAL

Jurnal Teknik Industri ◽

10.22219/jtiumm.vol11.no2.117-122 ◽

2012 ◽

Vol 11 (2) ◽

pp. 117

Author(s):

PRIYO HERU ADIWIBOWO

Keyword(s):

Flow Pattern ◽

Power Plants ◽

Bubbly Flow ◽

Digital Camera ◽

Vertical Pipe ◽

Two Phase ◽

Pressurized Water ◽

Industrial Facilities ◽

Multi Phase ◽

Pattern Visualization

Multi-phase flows are widely encountered in several engineering and industrial facilities, such as conventional steam power plants, evaporators and condensers, pressurized-water nuclear reactors, a wide variety of petroleum industries, chemicals and food processing industries. Surely, in the complex pipeline installation of these systems, vertical pipe will be commonly used for pipe connection. The purpose of this work is to investigate the flow pattern of gas-liquid two phase in the vertical pipe. Experiments will be performed in a 36 mm ID acrylic pipe vertical. Superifical liquid velocities and volumetric gas quality will be varied 0.3~1,1 m/s and 0.05~0.2 respectively. Digital camera will be used for flow pattern visualization in the vertical pipe. It was observed that effect of vertical pipe on flow pattern formed cluster bubbly flow for low volumetric gas quality with high superifical liquid velocities. For superifical liquid velocities with medium volumetric gas quality formed homogeneous bubbly flow and high volumetric gas quality is dense bubbly flow.

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TWO-DIMENSIONAL VELOCITY VECTOR PROFILE MEASUREMENT ON BUBBLY FLOW USING ULTRASONIC TECHNIQUE

The Proceedings of the International Conference on Nuclear Engineering (ICONE) ◽

10.1299/jsmeicone.2019.27.2257 ◽

2019 ◽

Vol 2019.27 (0) ◽

pp. 2257

Author(s):

Wongsakorn Wongsaroj ◽

Jevin Tanius Owen ◽

Hideharu Takahashi ◽

Natee Thong-un ◽

Hiroshige Kikura

Keyword(s):

Velocity Vector ◽

Bubbly Flow ◽

Profile Measurement ◽

Ultrasonic Technique ◽

Two Dimensional

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Development of Prediction Technology of Two-Phase Flow Dynamics Under Earthquake Acceleration (6) Numerical Simulation of Bubble Deformation Near Wall Under Accelerating Condition

Volume 3: Thermal-Hydraulics; Turbines, Generators, and Auxiliaries ◽

10.1115/icone20-power2012-54663 ◽

2012 ◽

Author(s):

Hiroyuki Yoshida ◽

Taku Nagatake ◽

Kazuyuki Takase ◽

Akiko Kaneko ◽

Hideaki Monji ◽

...

Keyword(s):

Flow Rate ◽

Nuclear Reactor ◽

Two Phase Flow ◽

Nuclear Reactors ◽

Bubbly Flow ◽

Flow Simulation ◽

Structural Safety ◽

Phase Flow ◽

Two Phase ◽

Safety Operation

Earthquake is one of the most serious phenomena for safety of a nuclear reactor in Japan. Therefore, structural safety of nuclear reactors has been studied and nuclear reactors were contracted with structural safety for a big earthquake. However, it is not enough for safety operation of nuclear reactors because thermal-fluid safety is not confirmed under the earthquake. For instance, behavior of gas-liquid two-phase flow is unknown under the earthquake conditions. Especially, fluctuation of void faction is an important factor for the safety operation of the nuclear reactor. In the previous work, fluctuation of void faction in bubbly flow was studied experimentally and theoretically to investigate the stability of the bubbly flow. In such studies, flow rate or void fraction fluctuations were given to the steady bubbly flow. In case of the earthquake, the fluctuation is not only the flow rate, but also body force on the two-phase flow and shear force through a pipe wall. Interactions of gas and liquid through their interface also act on the behavior of the two-phase flow. The fluctuation of the void fraction is not clear for such complicated situation under the earthquake. Therefore, the behavior of gas-liquid two-phase flow is investigated experimentally and numerically in a series of study. In this study, to develop the prediction technology of two-phase flow dynamics under earthquake acceleration, a detailed two-phase flow simulation code with an advanced interface tracking method TPFIT was expanded to two-phase flow simulation under earthquake conditions. In this paper, outline of expansion of the TPFIT to simulate detailed two-phase flow behavior under the earthquake condition was shown. And the bubbly flow in a horizontal pipe excited by oscillation acceleration and under the fluctuation of the liquid flow was simulated by using expanded TPFIT. Predicted deformation of bubbles near wall was compared with measured results under flow rate fluctuation and structural vibration.

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Behavior of Bubbles Separated by a Cross-Shaped Obstacle Placed in a Circular Flow Channel

Volume 7: Fluids Engineering ◽

10.1115/imece2017-71810 ◽

2017 ◽

Author(s):

Kazuyuki Takase ◽

Hiep H. Nguyen ◽

Gaku Takase ◽

Yoshihisa Hiraki

Keyword(s):

High Speed ◽

Nuclear Reactor ◽

Two Phase Flow ◽

Flow Direction ◽

Flow Behavior ◽

Bubbly Flow ◽

Wire Mesh ◽

Phase Flow ◽

Two Phase ◽

Validation Data

Clarifying two-phase flow characteristics in a nuclear reactor core is important in particular to enhance the thermo-fluid safety of nuclear reactors. Moreover, bubbly flow data in subchannels with spacers are needed as validation data for current CFD codes like a direct two-phase flow analysis code. In order to investigate the spacer effect on the bubbly flow behavior in a subchannel of the nuclear reactor, bubble dynamics around the simply simulated spacer was visually observed by a high speed camera. Furthermore, the void fraction and interfacial velocity distributions just behind the simulated spacer were measured quantitatively by using a wire-mesh sensor system with three wire-layers in the flow direction. From the present study, bubble separation behavior dependence upon the spacer shape was clarified.

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