The Numerical Simulation and Optimal Design of Nozzle Jet for Gas-Fluid Two Phase Flow

Taking a nozzle jet for gas-fluid phase flow as a research object, the influences of the main structural parameters on the vacuum in the internal suction volume are analyzed. Utilizing the software FLUENT to simulate the gas-liquid two-phase flow in nozzle jet with different structural parameters, the pressure distributions are obtained and the relationship between the structural parameters and the vacuum in the suction volume is concerned. The results show that the vacuum in the suction volume of jet reaches the maximum when these structural parameters are some certain values. The research is helpful for the optimal design and performance testing of nozzle jets.

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Conditions of gas–solid two-phase flow formed in a vertical screw conveyor

Advances in Mechanical Engineering ◽

10.1177/1687814018797761 ◽

2018 ◽

Vol 10 (9) ◽

pp. 168781401879776

Author(s):

Sun Xiaoxia ◽

Meng Wenjun ◽

Yuan Yuan

Keyword(s):

Gas Flow ◽

Two Phase Flow ◽

Screw Conveyor ◽

Particle State ◽

Phase Flow ◽

Two Phase ◽

Pressure Distributions ◽

Fluent Simulation ◽

Screw Diameter ◽

The Relationship

This study investigates the velocity and pressure distributions of gas flow field in a vertical screw conveyor through EDEM simulation. Results show that the vertical velocity of gas is the highest and that the minimum pressure is negative, which is at the exit, thereby aiding in the upward transportation of particles. The particle state in the vertical screw conveyor is obtained without considering gas (EDEM simulation) and by considering gas (EDEM + FLUENT simulation), respectively. Investigation of the relationship among the screw critical speed, screw diameter, and particle size shows that the conditions of gas–solid two-phase flow form in the vertical screw conveyor. A test is designed to verify the correctness of the conclusions. The results of this study lay a foundation for the development of design methods based on gas–solid two-phase flow in a vertical screw conveyor.

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Mixing Characteristics of a Two-Phase Flow (Gas-Liquid) Microchannel Mixer

ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, Volume 2 ◽

10.1115/icnmm2011-58238 ◽

2011 ◽

Author(s):

Tarek Abdel-Salam ◽

Srikanth Pidugu

Keyword(s):

Reynolds Number ◽

Two Phase Flow ◽

Bubble Formation ◽

Width Ratio ◽

Phase Flow ◽

Two Phase ◽

Bubble Generation ◽

Air Bubble ◽

And Performance ◽

Actual Shape

Multiphase phase flows occur in many engineering and bio-medical applications. Bubble formation in microchannels can be beneficial or harmful depending upon their influence on the operation and performance of microfludic devices. Potential uses of bubble generation found in many applications such as microreactors, micropump, and micromixers. In the present work the flow and mixing process in a passive microchannel mixer were numerically investigated. Effects of velocity, and inlet width ratio (Dgas/Dliquid) on the two phase flow were studied. Numerical results are obtained for 2-dimensional and 3-dimesional cases with a finite volume CFD code and using structured grids. Different liquid-gas Reynolds number ratios (Reliquid/Regas) were used ranging from 4 to 42. In addition, three values of the inlet width ratio (Dgas/Dliquid) were used. Results for the 3-D cases capture the actual shape of the air bubble with the thin film between the bubble and the walls. Also, increasing Reliquid increases the rate of the development of the air bubble. The bubble length increases with the increase of Dgas/Dliquid. For the same values of Re, the rate of growth of the bubble increases with the increase of Dgas/Dliquid. Finally, a correlation is provided to predict the length of the bubble with liquid-gas Reynolds number ratio (Reliquid/Regas) and tube width.

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New Experimental Data and Analysis for Two-Phase Flow-Induced Vibration of Tube Bundles: Preliminary Results

Flow-Induced Vibration ◽

10.1115/pvp2003-2071 ◽

2003 ◽

Cited By ~ 1

Author(s):

Deepanjan Mitra ◽

Vijay K. Dhir ◽

Ivan Catton

Keyword(s):

Two Phase Flow ◽

Structural Parameters ◽

Cross Flow ◽

Instability Criterion ◽

Phase Flow ◽

Flow Induced Vibration ◽

Two Phase ◽

Void Fractions ◽

Comparison Of The Results ◽

Square Array

In the past, fluid-elastic instability in two-phase flow has been largely investigated with air-water flow. In this work, new experiments are conducted in air-water cross-flow with a fully flexible 5 × 3 normal square array having pitch-to-diameter ratio of 1.4. The tubes have a diameter of 0.016 m and a length of 0.21 m. The vibrations are measured using strain gages installed on piano wires used to suspend the tubes. Experiments are carried out for void fractions from 0%–30%. A comparison of the results of the current tests with previous experiments conducted in air-water cross-flow shows that instability occurs earlier in a fully flexible array as compared to a flexible tube surrounded by rigid tubes in an array. An attempt is made to separate out the effects of structural parameters of three different experimental datasets by replotting the instability criterion by incorporating the instability constant K, in the reduced velocity parameter.

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CFD Simulation of Two-Phase Flow in a Downhole Venturi Meter

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.130-134.3644 ◽

2011 ◽

Vol 130-134 ◽

pp. 3644-3647

Author(s):

Ding Feng ◽

Si Huang ◽

Yu Hui Guan ◽

Wei Guo Ma

Keyword(s):

Optimal Design ◽

Pressure Drop ◽

Flow Field ◽

Cfd Simulation ◽

Two Phase Flow ◽

Flow Simulation ◽

Phase Flow ◽

Feed Flow Rate ◽

Two Phase ◽

Oil Water

This work performs an oil-water two-phase flow simulation in a downhole Venturi meter to investigate the flow field and pressure characteristics with different flow and oil-water ratios. The relation between the pressure drop and the feed flow rate in the flowmeter is investigated for its optimal design.

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