Critical Sand Deposition Velocity in Intermittent Flow – Models Evaluation

2019 ◽  
Author(s):  
Ramin Dabirian ◽  
Mobina Mohammadikharkeshi ◽  
Ram Mohan ◽  
Ovadia Shoham
Keyword(s):  
Deposition Velocity ◽  
Intermittent Flow ◽  
Flow Models ◽  
Sand Deposition

Investigation of Critical Sand-Deposition Velocity in Horizontal Gas/Liquid Stratified Flow

2017 ◽  
Vol 32 (03) ◽  
pp. 218-227 ◽  
Author(s):  
Roberto Ibarra ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Deposition Velocity ◽  
Stratified Flow ◽  
Sand Deposition

Sand Transport in Slightly Upward Inclined Multiphase Flow

2018 ◽  
Vol 140 (7) ◽  
Author(s):  
Ramin Dabirian ◽  
Ram Mohan ◽  
Ovadia Shoham ◽  
Gene Kouba
Keyword(s):  
Flow Regime ◽  
Water Flow ◽  
Deposition Velocity ◽  
Stratified Flow ◽  
Flow Regimes ◽  
Test Facility ◽  
Sand Transport ◽  
Deposition Condition ◽  
Sand Flow ◽  
Sand Deposition

In order to assess the critical sand deposition condition, a unique 4-in ID test facility was designed and constructed, which enables the pipe to be inclined 1.5 deg upward. Experiments were conducted with air–water-glass beads at low sand concentrations (< 10,000 ppm), and the air and water flow rates were selected to ensure stratified flow regime along the pipe. At constant superficial liquid velocity, the gas velocity was reduced to find the critical sand deposition velocity. Six sand flow regimes are identified, namely, fully dispersed solid flow, dilute solids at the wall, concentrated solids at the wall, moving dunes, stationary dunes, and stationary bed. The experimental results reveal that sand flow regimes under air–water stratified flow are strong functions of phase velocities, particle size, and particle concentration. Also, the results show that air–water flow regime plays an important role in particle transport; slug flow has high capability to transport particles at the pipe bottom, while the stratified flow has high risk of sand deposition. As long as the sand dunes are observed at the pipe bottom, the critical sand deposition velocities slightly increase with concentrations, while for stationary bed, the critical velocity increases exponentially with concentration.

Numerical Simulation and Modeling of Critical Sand-Deposition Velocity for Solid/Liquid Flow

2018 ◽  
Vol 33 (04) ◽  
pp. 866-878 ◽  
Author(s):  
Ramin Dabirian ◽  
Hadi Arabnejad Khanouki ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Numerical Simulation ◽  
Liquid Flow ◽  
Deposition Velocity ◽  
Simulation And Modeling ◽  
Solid Liquid ◽  
Sand Deposition

Assessment of Prototypic and Closed Loop Operation During Pulse Jet Mixer Tests With Non-Cohesive Solids to Develop Scale-Up Relationships

2011 ◽  
Author(s):  
Judith Ann Bamberger ◽  
Michael J. Minette ◽  
Perry A. Meyer ◽  
James A. Fort ◽  
Ellen B. K. Baer
Keyword(s):  
Waste Treatment ◽  
Scale Up ◽  
Treatment Plant ◽  
Intermittent Flow ◽  
Flow Models ◽  
Waste Treatment Plant ◽  
Flow Through ◽  
Solids Mixing ◽  
Pulse Jet ◽  
Reciprocating Flow

The Hanford Waste Treatment Plant (WTP) in Richland, Washington is applying pulse jet mixer (PJM) technology for slurry mixing applications requiring solids mixing, solids suspension, fluid blending, and release of gases generated by radiolysis and thermal processes. Experiments were conducted to investigate pulse jet mixer performance in two different experimental configurations: one using intermittent flow through the pulse tube with non-prototypic refill and the other with prototypic reciprocating flow. Models developed to predict the critical suspension velocity (UCS), cloud height, and concentration based on the intermittent flow data. This model under predicted the UCS condition for data obtained using prototypic reciprocating flow. When an adjustment to the settling velocity was incorporated into the model to address the effects of intermittent flow, the resulting reciprocating flow model more closely matched the experimental data.

Sand Flow Regimes in Slightly Upward Inclined Gas-Liquid Stratified Flow

2016 ◽  
Author(s):  
Ramin Dabirian ◽  
Ram S. Mohan ◽  
Ovadia Shoham ◽  
Gene Kouba
Keyword(s):  
Flow Regime ◽  
Water Flow ◽  
Liquid Velocity ◽  
Sand Dunes ◽  
Deposition Velocity ◽  
Stratified Flow ◽  
Test Facility ◽  
Deposition Condition ◽  
Sand Particles ◽  
Sand Deposition

Sand particles are produced from the reservoir with low formation strength. A sand management system is required to be designed to keep the sand particles moving so as to prevent them from accumulating in the pipeline. Operating under unnecessarily high fluid velocities is not cost effective, moreover, it can lead to equipment failure; therefore, it is required to find the minimum velocity, known as critical sand deposition velocity, to keep the particles constantly moving. In order to assess the critical sand deposition condition, a unique test facility was designed and constructed with 4-in ID PVC pipeline, which enables the pipe to be inclined 1.5° upward. Experiments were conducted with air-water-glass beads at low sand concentrations (< 10,000 ppm), and the air and water flow rates were selected to ensure stratified flow regime along the pipe. At constant superficial liquid velocity the gas velocity was reduced to find the critical sand deposition velocity. The experimental results reveal that air-water flow regime plays an important role in particle transport; slug flow has high capability to transport particles at the pipe bottom, while the stratified flow has high risk of sand deposition. As long as the sand dunes are observed at the pipe bottom, the critical sand deposition velocities slightly increase with concentrations, while for stationary bed, the critical velocity increases exponentially with concentration.

Avalanche Stratification - Experimental Tests of the “Metastable Wedge” and “Continuous Flow” Models

2000 ◽  
Vol 627 ◽  
Author(s):  
M. E. Swanson ◽  
M. Landreman ◽  
J. Michel ◽  
J. Kakalios
Keyword(s):  
Continuous Flow ◽  
Granular Media ◽  
Experimental Tests ◽  
Coarse Sand ◽  
Angle Of Repose ◽  
Flow Models ◽  
Maximum Angle ◽  
Stratification Effect ◽  
Upward Moving ◽  
Moving Layer

ABSTRACTWhen an initially homogeneous binary mixture of granular media such as fine and coarse sand is poured near the closed edge of a “quasi-two-dimensional” Hele-Shaw cell consisting of two vertical transparent plates held a narrow distance apart, the mixture spontaneously forms alternating segregated layers. Experimental measurements of this stratification effect are reported in order to determine which model, one which suggests that segregation only occurs when the granular material contained within a metastable heap between the critical and maximum angle of repose avalanches down the free surface, or one for which the segregation results from smaller particles becoming trapped in the top surface and being removed from the moving layer during continuous flow. The result reported here indicate that the Metastable Wedge model provides a natural explanation for the initial mixed zone which precedes the formation of the layers, while the Continuous Flow model explains the observed upward moving kink of segregated material for higher granular flux rates, and that both mechansims are necessary in order to understand the observed pairing of segregated layersfor intermediate flow rates and cell separations.

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