Distribution of velocity components and liquid holdup in short vertical tubes with swirl bodies in the inlet part of the tube at cocurrent gas-liquid flow

The axial and tangential velocity components and local liquid holdup rates have been measured in vertical tubes with swirl bodies located in the inlet part of the tube. The tubes were of 70 mm I.D. and H/D = 10-23. The air-water flow was directed upward. Superficial gas velocity was wG = 14-35 m s-1 and specific liquid load QLE = 15-65 m3 m-2 h-1. In the experiments, the blade angle of the swirl body and the liquid inlet have been altered. The resulting centrifugal moments were correlated with friction factors.

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Homogeneous and re-circulatory gas–liquid flow in a bubble column: A numerical investigation using OpenFOAM

SN Applied Sciences ◽

10.1007/s42452-021-04569-6 ◽

2021 ◽

Vol 3 (6) ◽

Author(s):

Saroj K. Panda

Keyword(s):

Liquid Flow ◽

Bubble Size ◽

Bubble Column ◽

Cfd Model ◽

Gas Velocity ◽

Drag Forces ◽

Circulatory Flow ◽

Gas Liquid Flow ◽

Lift And Drag ◽

Superficial Gas Velocity

AbstractThis work presents the influence of the sparger opening area, gas velocity, and bubble size on hydrodynamics and transition of the flow regime from uniform to re-circulatory in a rectangular bubble column using OpenFOAM. In the course of development of the model, the effect of several drag closures and lift on the predictability of the CFD model was studied by comparing the predictions with published experimental results. Reynolds number-based drag closure was found to be suitable for uniform sparger whereas Tsuchiya drag (Tsuchiya et al. in Chem Eng Sci 52:3053–3066, 1997. https://doi.org/10.1016/S0009-2509(97)00127-9) was used to simulate gas–liquid flow for other spargers. Simulations were performed for seven different spargers with opening area 18–100% (superficial gas velocity of 2.9–5.8 cm/s) and bubble size of 2–8 mm. The smaller opening area and higher gas velocity promote the re-circulatory flow in the bubble column. Change in bubble size affects the hydrodynamics due to change in lift and drag forces.

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Two-phase (gas—liquid) flow phenomena—I Pressure drop and hold-up for two-phase flow in vertical tubes

Chemical Engineering Science ◽

10.1016/0009-2509(60)87004-2 ◽

1960 ◽

Vol 12 (2) ◽

pp. 109-126 ◽

Cited By ~ 45

Author(s):

G.H. Anderson ◽

B.G. Mantzouranis

Keyword(s):

Pressure Drop ◽

Liquid Flow ◽

Two Phase Flow ◽

Phase Flow ◽

Two Phase ◽

Flow Phenomena ◽

Gas Liquid Flow ◽

Vertical Tubes

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Frictional Pressure Drop and Liquid Holdup of Churn Flow in Vertical Pipes with Different Viscosities

Geofluids ◽

10.1155/2021/6661014 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Zilong Liu ◽

Yubin Su ◽

Ming Lu ◽

Zilong Zheng ◽

Ruiquan Liao

Keyword(s):

Pressure Drop ◽

Liquid Velocity ◽

Gas Velocity ◽

Liquid Holdup ◽

Two Phase ◽

Frictional Pressure Drop ◽

Viscous Oil ◽

Predicted Values ◽

Superficial Gas Velocity ◽

Churn Flow

Churn flow commonly exists in the pipe of heavy oil, and the characteristics of churn flow should be widely understood. In this paper, we carried out air and viscous oil two-phase flow experiments, and the diameter of the test section is 60 mm. The viscosity range of the oil was 100~480 mPa·s. Based on the measured liquid holdup and pressure drop data of churn flow, it can be concluded that, due to the existence of liquid film backflow, positive and negative frictional pressure drop can be found and the change of frictional pressure drop with the superficial gas velocity is related to superficial liquid velocity. With the increase of viscosity, the change rate of frictional pressure drop increases with the increase of the superficial gas velocity. Combining our previous work and the Taitel model, we proposed a new pressure drop model for viscous oil-air two-phase churn flow in vertical pipes. By comparing the predicted values of existing models with the measured pressure drop data, the proposed model has better performance in predicting the pressure drop.

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Experimental Study on Flow Patterns and Pressure Drop of Decaying Swirling Gas-Liquid Flow in a Vertical Pipe

Volume 1: Beyond Design Basis; Codes and Standards; Computational Fluid Dynamics (CFD); Decontamination and Decommissioning; Nuclear Fuel and Engineering; Nuclear Plant Engineering ◽

10.1115/icone2020-16484 ◽

2020 ◽

Author(s):

Jiarong Zhang ◽

Li Liu ◽

Shuai Liu ◽

Hanyang Gu

Keyword(s):

Pressure Drop ◽

Flow Regime ◽

Liquid Flow ◽

High Speed ◽

Phase Distribution ◽

Swirling Flow ◽

Tangential Velocity ◽

High Speed Camera ◽

Vertical Pipe ◽

Gas Liquid Flow

Abstract Vertical swirling gas-liquid flow is a kind of complex two-phase flow containing a nonzero tangential velocity component in engineering applications. The accurate flow regime characterization, phase distribution information and pressure drop data about vertical swirling flow are the basis for the optimization of steam generator (SG), which can greatly reduce the cost and improve the safety of nuclear plants. To get these key parameters of swirling vertical flow, we have made a comprehensive visualization experiment in a vertical pipe with 30mm diameter and 5m length by high-speed camera. The experimental pipe is separated into swirling part and non-swirling part. We have set three observation section with different vertical heights in the swirling part. Changing the flow rate of water and gas, different swirling flow pattern photos can be captured by high-speed camera. Based on the photos of different positions and image-processing MATLAB code, we can get three flow regime maps and figure out the decaying law of swirling gas-liquid flow. The pressure drop can be recorded by rotameter at each position. The decaying law of pressrure drop can be concluded from it. These data can be a guide for designing gas-liquid separator in SG to improve the efficiency of nuclear plant.

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Flooding behaviour in countercurrent gas-liquid flow in vertical tubes with turbulence promoters

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2016.08.017 ◽

2017 ◽

Vol 115 ◽

pp. 1363-1371

Author(s):

Klaus Spindler

Keyword(s):

Liquid Flow ◽

Gas Liquid Flow ◽

Vertical Tubes

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

Fluids Engineering ◽

10.1115/imece2005-82885 ◽

2005 ◽

Cited By ~ 1

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.

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Design and Performance of Slug Damper

Journal of Energy Resources Technology ◽

10.1115/1.3000137 ◽

2008 ◽

Vol 130 (4) ◽

Cited By ~ 1

Author(s):

Antonio Reinoso ◽

Luis E. Gomez ◽

Shoubo Wang ◽

Ram S. Mohan ◽

Ovadia Shoham ◽

...

Keyword(s):

Flow Rate ◽

Liquid Flow ◽

Liquid Flow Rate ◽

Liquid Velocity ◽

Flow Behavior ◽

Mechanistic Model ◽

Gas Velocity ◽

Flow Loop ◽

Two Phase ◽

Superficial Gas Velocity

This study investigates theoretically and experimentally the slug damper as a novel flow conditioning device, which can be used upstream of compact separation systems. In the experimental part, a 3 in. ID slug damper facility has been installed in an existing 2 in. diameter two-phase flow loop. This flow loop includes an upstream slug generator, a gas-liquid cylindrical cyclone (GLCC©, ©The University of Tulsa, 1994) attached to the slug damper downstream and a set of conductance probes for measuring the propagation of the dissipated slug along the damper. Over 200 experimental runs were conducted with artificially generated inlet slugs of 50 ft length (Ls/d=300) that were dumped into the loop upstream of the slug damper, varying the superficial liquid velocity between 0.5 ft/s and 2.5 ft/s and superficial gas velocity between 10 ft/s and 40 ft/s (in the 2 in. inlet pipe) and utilizing segmented orifice opening heights of 1 in., 1.5 in., 2 in., and 3 in. For each experimental run, the measured data included propagation of the liquid slug front in the damper, differential pressure across the segmented orifice, GLCC liquid level, GLCC outlet liquid flow, and static pressure in the GLCC. The data show that the slug damper/GLCC system is capable of dissipating long slugs, narrowing the range of liquid flow rate from the downstream GLCC. Also, the damper capacity to process large slugs is a strong function of the superficial gas velocity (and mixture velocity). The theoretical part includes the development of a mechanistic model for the prediction of the hydrodynamic flow behavior in the slug damper. The model enables the predictions of the outlet liquid flow rate and the available damping time, and in turn the prediction of the slug damper capacity. Comparison between the model predictions and the acquired data reveals an accuracy of ±30% with respect to the available damping time and outlet liquid flow rate. The developed model can be used for design of slug damper units.

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