Pattern transition of a gas–liquid flow with zero liquid superficial velocity in a vertical tube

The gas-liquid flow inside a horizontal static mixer was numerically investigated by using Euler-Euler Computational Fluid Dynamics (CFD) simulations. The results confirm that the liquid superficial velocity plays a significant role on the mixing behavior of the gas and liquid. The mixing behavior in this present study at a liquid superficial velocity of 0.2 m/s was the worst both axially and radially. Increasing the liquid superficial velocity significantly improve the mixing between gas and liquid. However, the unwanted gas layer still can be found at the superficial liquid velocity less than 0.8 m/s. A good mixing behavior in this study was achieved at a relatively high velocity (i.e. larger than 0.8 m/s).

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Gas-Liquid Flow in a Vertical Pipe Equipped with a Double Helical Swirl Separator Element

Jurnal Inotera ◽

10.31572/inotera.vol5.iss2.2020.id110 ◽

2020 ◽

Vol 5 (2) ◽

pp. 92-99

Author(s):

Ryan Anugrah Putra ◽

Akhlisa Nadiantya Aji Nugroho ◽

Aditya Ramadhona ◽

Erick Wisnu Kuncoro Baroto

Keyword(s):

Fluid Dynamics ◽

Liquid Flow ◽

Flow Behavior ◽

Superficial Velocity ◽

Separation Condition ◽

Vertical Pipe ◽

Computational Fluid Dynamics Cfd ◽

Gas Liquid Flow ◽

Liquid Flows ◽

Separation Behavior

Two different gas-liquid flow behavior downstream a double helical swirl element inside a vertical pipe was observed in our preliminary experiment. The present Computational Fluid Dynamics (CFD) study confirms that the dynamics of gas-liquid flows inside the swirl separator is highly influenced by the liquid superficial velocity. The separation behavior in this work at a liquid superficial velocity of 0.1 m/s was the worst both axially and radially since the gas core cannot be sustained up to the outlet. The separation condition was improved by the increase of the liquid superficial velocity. The best separation condition in this study was achieved at the liquid superficial velocity of 1.0 m/s where the dense gas core can be maintained up to the outlet.

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Flow Configure in Vertical 180 Degree Turning Duct

10.1115/imece2001/htd-24182 ◽

2001 ◽

Author(s):

Lu Yuanwei ◽

Zhou Fangde ◽

Wang Yueshe ◽

Qian Huanqun ◽

Hu Zhihua

Keyword(s):

Flow Pattern ◽

Liquid Flow ◽

Two Phase Flow ◽

Vertical Tube ◽

Experimental Result ◽

Phase Flow ◽

Two Phase ◽

Vertical Part ◽

Flow Situation ◽

Gas Liquid Flow

Abstract Bend is applied in many industries, which exert an influence on fluid and make the flow complicate. The second flow caused by the bend is strong enough that the flow behind it very long can be affected, so it is hard to make the flow in it steady. The long-term unsteady flow can make the pipe fatigue, so make the tube crack and leak. It is important to improve this situation. In this paper a throttle is built in the exit of the bend to control the non-homogeneous flow inside the bend, which can overcome the disadvantage of bend in industrial application. Through computed the flow field behind the bend by water, we can see that the throttle can improve the flow situation and make the flow steady behind it. Applying this method to the gas-liquid flow, the experimental result showed that the void fraction behind the bend is alike the fully developed flow. It means that the throttle can improve the two-phase flow situation in the invert U bend. At last the gas-liquid flow pattern in-bend was studied by experiment and built the flow pattern map in the vertical parts of the invert U bend. It was found that the flow pattern in the vertical part of invert U bend is different from the fully developed gas-liquid flow in vertical tube. The throttle built in the bend make the unsteady region of two-phase flow being reduced.

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