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

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

Volume 4: Fluid Measurement and Instrumentation; Micro and Nano Fluid Dynamics ◽

10.1115/ajkfluids2019-5636 ◽

2019 ◽

Author(s):

Wongsakorn Wongsaroj ◽

Hideharu Takahashi ◽

Hiroshige Kikura ◽

Natee Thong-un

Keyword(s):

Velocity Distribution ◽

Velocity Vector ◽

Nuclear Reactor ◽

Bubbly Flow ◽

Profile Measurement ◽

Vertical Pipe ◽

Two Phase ◽

Ultrasound Technique ◽

Image Velocimetry ◽

Flow Apparatus

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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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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Exact solutions for two phase vertical pipe flow

Mechanics Research Communications ◽

10.1016/0093-6413(92)90003-s ◽

1992 ◽

Vol 19 (1) ◽

pp. 7-13 ◽

Cited By ~ 25

Author(s):

Manohar Gadiraju ◽

John Peddieson ◽

Sastry S. Munukutla

Keyword(s):

Exact Solutions ◽

Pipe Flow ◽

Vertical Pipe ◽

Two Phase

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CFD Modeling of Subcooled Boiling in Vertical Bubbly Flow Condition Using ANSYS CFX 12

18th International Conference on Nuclear Engineering: Volume 4, Parts A and B ◽

10.1115/icone18-30206 ◽

2010 ◽

Cited By ~ 2

Author(s):

Filippo Pellacani ◽

Silvana Matturro Mestre ◽

Sergio Chiva Vicent ◽

Rafael Macian Juan

Keyword(s):

Void Fraction ◽

Lift Force ◽

Bubbly Flow ◽

Cfd Modeling ◽

Computational Domain ◽

Subcooled Boiling ◽

Vertical Pipe ◽

Mean Values ◽

Drag Forces ◽

Ansys Cfx

Subcooled boiling in upward non-isothermal turbulent bubbly flow in tubes is numerically modeled using ANSYS-CFX 12 in this contribution. The approach is based on the RPI wall boiling model developed by Kurul and Podowski [1]. The interfacial non-drag forces are also investigated and included in the model. The Antal [5] model with different coefficients is used for the wall lubrication force. The lift force was calculated in two ways, with the Tomiyama model [4] and based on a constant value. The void fraction axial profiles for high pressure subcooled boiling in tubes are compared against the experimental data of Bartolomej [17] [18]. The pressure varies from 3 up to 6.89 MPa and the wall heat flux from 0.38 to 1.2 MW m−2. The mass flux range is between 900 and 1500 kg s−1m−2. The computational domain has up to 70000 nodes, and represents one eighth of a vertical pipe. In general, the models give predictions in close agreement with experimental results if the axial mean values are considered. The main difficulties for the simulation are observed for flow in transition to flow regimes with high void fraction, when the bubbly flow is not able to maintain the spherical condition of the bubbles, which is a requirement of the boiling models.

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