Experimental Study on Flow Patterns of Decaying Swirling Gas-Liquid Flow in a Horizontal Pipe

2020 ◽  
Author(s):  
Shuai Liu ◽  
Li Liu ◽  
Jiarong Zhang ◽  
Hanyang Gu
Keyword(s):  
Flow Pattern ◽  
Liquid Flow ◽  
Separation Efficiency ◽  
Swirling Flow ◽  
Flow Patterns ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Gas Removal ◽  
Swirl Vane ◽  
Gas Liquid Flow

Abstract Swirling flow is one of the well-recognized techniques to control the working process. This special flow is widely adopted in swirl vane separators in nuclear steam generator (SG) for water droplet separation and the fission gas removal system in Thorium Molten Salt Reactor (TMSR) for gas bubble separation. Since the parameters such as separation efficiency, pressure drop and mass and heat transfer rate are strongly dependent on the flow pattern, the accurate prediction of flow patterns and their transitions is extremely important for the proper design, operation and optimization of swirling two-phase flow systems. In this paper, using air and water as working fluids, a visualization experiment is carried out to study the gas-liquid flow in a horizontal pipe containing a swirler with four helical vanes. The test pipe is 5 m in length and 30 mm in diameter. Firstly, five typical flow patterns of swirling gas-liquid flow at the outlet of the swirler are classified and defined, these being spiral chain, swirling gas column, swirling intermittent, swirling annular and swirling ribbon flow. Being affected by the different gas and liquid flow rate of non-swirling flow, it is found that the same non-swirling flow can change into different swirling flow patterns. After that, the evolution of various swirling flow patterns along the streamwise direction is analyzed considering the influence of swirl attenuation. The results indicate that the same swirling flow pattern can transform into a variety of swirling flow patterns and subsequent non-swirling flow patterns. Finally, the flow pattern maps at different positions downstream of the swirler are presented.

Surfactant Use for Slug Flow Pattern Suppression in a Horizontal Pipe

2003 ◽  
Author(s):  
R. J. Wilkens ◽  
S. R. Glassmeyer ◽  
G. J. Rosebrock ◽  
K. M. Storage ◽  
T. M. Storage
Keyword(s):  
Flow Pattern ◽  
Liquid Flow ◽  
Pipe Flow ◽  
Slug Flow ◽  
Flow Patterns ◽  
Flow Transition ◽  
Horizontal Pipe ◽  
Surfactant Additive ◽  
Gas Liquid Flow

A set of experiments was performed to study flow pattern suppression in gas-liquid pipe flow by means of surfactant additive. Results suggest that addition of the surfactant to gas-liquid flow significantly reduces the occurrence of slug flow. In addition, previously unreported flow patterns were observed to exist between slug and dispersed bubble flows. It is concluded that new mechanisms for slug flow transition need to be considered.

Surfactant Use for Slug Flow Pattern Suppression and New Flow Pattern Types in a Horizontal Pipe

2005 ◽  
Vol 128 (1) ◽  
pp. 164-169 ◽  
Author(s):  
R. J. Wilkens ◽  
D. K. Thomas ◽  
S. R. Glassmeyer
Keyword(s):  
Flow Pattern ◽  
Liquid Flow ◽  
Pipe Flow ◽  
Slug Flow ◽  
Flow Patterns ◽  
Flow Transition ◽  
Water Pipe ◽  
Horizontal Pipe ◽  
Surfactant Additive ◽  
Gas Liquid Flow

A set of experiments was performed to study flow pattern suppression in horizontal air-water pipe flow by means of surfactant additive. Results suggest that addition of the surfactant to the gas-liquid flow significantly reduces the occurrence of slug flow. In addition, previously unreported flow patterns were observed to exist between slug and dispersed bubble flows. It is concluded that new mechanisms for slug flow transition need to be considered.

Non-Invasive Method for Velocity and Slug Length Measurements in Gas/Liquid Flow in Horizontal Pipes

2005 ◽  
Author(s):  
S. Al-Lababidi ◽  
M. L. Sanderson
Keyword(s):  
Liquid Flow ◽  
Liquid Velocity ◽  
Correlation Technique ◽  
Translational Velocity ◽  
Two Phase ◽  
Horizontal Pipe ◽  
Horizontal Pipes ◽  
Non Invasive ◽  
Gas Liquid Flow ◽  
Superficial Gas Velocity

A method was developed for the measurement of slug frequency, slug velocity and slug length of two-phase gas/liquid flow under slug conditions in 2-inch horizontal pipe. The method consists of two pairs of ultrasonic transducers with 1MHz frequency. Non-invasive detection for slugs was achieved over a range of (0.1–1 ms−1) superficial liquid velocity and (0.1–3 ms−1) superficial gas velocity. The slug translational velocity was measured using a cross correlation technique for the modulated ultrasonic signals received. The slug length was measured after measuring the slug time t(slug) and slug translational velocity. The slug parameters measured were extensively compared with conductivity probes measurements and experimental correlations.

Effect of Fluid Properties on Flow Patterns in Two-Phase Gas−Liquid Flow in Horizontal and Downward Pipes†

2011 ◽  
Vol 50 (2) ◽  
pp. 645-655 ◽  
Author(s):  
Christina Tzotzi ◽  
Vasilis Bontozoglou ◽  
Nikolaos Andritsos ◽  
Michael Vlachogiannis
Keyword(s):  
Liquid Flow ◽  
Flow Patterns ◽  
Two Phase ◽  
Fluid Properties ◽  
Gas Liquid Flow

scholarly journals Gas–liquid Flow Pattern Recognition Based on Wavelet Packet Energy Entropy of Vortex-induced Pressure Fluctuation

2013 ◽  
Vol 13 (2) ◽  
pp. 83-88 ◽  
Author(s):  
Zhiqiang Sun ◽  
Shuai Shao ◽  
Hui Gong
Keyword(s):  
Pattern Recognition ◽  
Flow Pattern ◽  
Liquid Flow ◽  
Pressure Fluctuation ◽  
Bluff Body ◽  
Flow Direction ◽  
Wavelet Packet ◽  
Flow Patterns ◽  
Energy Entropy ◽  
Gas Liquid Flow

Here we report a novel flow-pattern map to distinguish the gas-liquid flow patterns in horizontal pipes at ambient temperature and atmospheric pressure. The map is constructed using the coordinate system of wavelet packet energy entropy versus total mass flow rate. The wavelet packet energy entropy is obtained from the coefficients of vortex-induced pressure fluctuation decomposed by the wavelet packet transform. A triangular bluff body perpendicular to the flow direction is employed to generate the pressure fluctuation. Experimental tests confirm the suitability of the wavelet packet energy entropy as an ideal indicator of the gas-liquid flow patterns. The overall identification rate of the map is 92.86%, which can satisfy most engineering applications. This method provides a simple, practical, and robust solution to the problem of gas-liquid flow pattern recognition.

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