Theoretical Modeling of Central Air-Jet Pump Performance for Pneumatic Transportation of Bulk Solids

1999 ◽  
Vol 121 (2) ◽  
pp. 365-372 ◽  
Author(s):  
D. Wang ◽  
P. W. Wypych
Keyword(s):  
Analytical Procedure ◽  
Area Ratio ◽  
Jet Pump ◽  
Pump Performance ◽  
Bulk Solids ◽  
Air Jet ◽  
Performance Predictions ◽  
Jet Pumps ◽  
Pneumatic Transportation ◽  
Good Agreement

A mathematical model to predict the air-solids performance of central air-jet pumps has been developed based on the fundamentals of fluid and particle mechanics. The influence of throat entry configuration on performance has been incorporated into the analytical model by introducing a throat entry function and suction area ratio. Nondimensional parameters to represent air-solids jet pump performance has been defined and used in the analytical procedure. The performance predictions obtained by this model show good agreement with experimental results.

Experimental and numerical studies of the effect of area ratio and driving pressure on the performance of water and slurry jet pumps

2011 ◽  
Vol 226 (9) ◽  
pp. 2250-2266 ◽  
Author(s):  
Tarek Meakhail ◽  
Ibrahim Teaima
Keyword(s):  
Area Ratio ◽  
Driving Pressure ◽  
Operating Conditions ◽  
Jet Pump ◽  
Numerical Studies ◽  
Pumping Stations ◽  
Mixing Chamber ◽  
Jet Pumps ◽  
Different Diameters ◽  
Experimental Rig

The slurry jet pump with scouring nozzle system can be used in dredging of sites, which are difficult to access or need handling of equipments that are used for the intake of pumping stations under bridges and concrete water channels. This system is suitable for sand, silt, sludge, mud, and other organic materials. The aim of this study is to investigate the performance of water and slurry jet pumps. The effects of the pump-operating conditions and geometries on its performance were investigated. The experimental rig was constructed in such a way that the driving nozzle diameter can be changed. In this study, three different diameters of driving nozzles, 10, 12.7, and 16 mm, have been used with one mixing chamber of 25.4 mm diameter (i.e. three different area ratios of R = 0.155, 0.25, and 0.4). Also, the effect of driving pressure has been investigated. The results show that increasing the area ratio decreases the maximum mass flow ratio. The results of computational fluid dynamics were found to agree well with actual values obtained from the experimental water and slurry jet pump.

An Investigation of Ejector Design by Analysis and Experiment

1950 ◽  
Vol 17 (3) ◽  
pp. 299-309
Author(s):  
J. H. Keenan ◽  
E. P. Neumann ◽  
F. Lustwerk
Keyword(s):  
Experimental Data ◽  
Constant Pressure ◽  
Jet Pump ◽  
Pump Design ◽  
One Dimensional ◽  
Analytical Results ◽  
Constant Area ◽  
Jet Pumps ◽  
Good Agreement

Abstract A one-dimensional method of analysis of jet pumps or ejectors is presented. The analysis considers mixing of the primary and secondary streams at constant pressure, and mixing of the streams at constant area. For the analytical conditions considered, better performance can be obtained when constant-pressure mixing is employed. A comparison between experimental and analytical results shows good agreement over a broad range of variables. Some experimental data on the length of tube required for mixing of the two streams are presented. A method for jet-pump design is given.

Numerical Investigation of Geometric Factors for Design of High Performance Air-Jet Pumps Using in Vehicle-Mounted Vacuum Toilet

2011 ◽  
Vol 268-270 ◽  
pp. 46-50
Author(s):  
Fei Gao ◽  
Jing Xuan Zhou ◽  
Min Li
Keyword(s):  
High Performance ◽  
Operating Conditions ◽  
Cfd Model ◽  
Jet Pump ◽  
Air Jet ◽  
Geometric Factors ◽  
Constant Area ◽  
Jet Pumps ◽  
Computational Fluid Dynamics Cfd ◽  
Area Section

Air-jet pump as the pneumatic source of a vehicle-mounted vacuum toilet provides the vacuum to pump the fecal sewage out of toilet bowl via the compressed air passing through the pump under certain pressure. In this study, Computational Fluid Dynamics (CFD) technique is employed to investigate the effects of three important air-jet pump geometry parameters: the primary Nozzle Exit Position (NXP), the constant-area section length (L1) and the diffuser diverging angle (θ), on its performance. A CFD model is firstly established according to 1D analytical method, and then used to create 135 different air-jet pump geometries and tested under different operating conditions. The significance of this study is that these findings can be used to guide the adjustment of NXP, L1 and θ to obtain the best air-jet pump performance when the operating conditions are different.

Modelling of Slurry-Handling Piping Element Under Interference Conditions

Volume 3 ◽  
2004 ◽  
Author(s):  
Prem Chand ◽  
K. Govinda Rajulu ◽  
Y. Krishna Reddy
Keyword(s):  
Particle Diffusion ◽  
Test Rig ◽  
Jet Pump ◽  
Two Phase ◽  
New Approach ◽  
Jet Pumps ◽  
Flow Through ◽  
Extensive Experimental Data ◽  
Fluid Interaction ◽  
Layer Concept

The paper presents a new approach to predict the two-phase performance of jet-pumps under interference conditions. We limit our study mainly to diffuser and transport regions of the jet pump. The five essential pre-requisites which form the backbone of our approach are a fairly generalized and accurate approach to (i) solid-fluid interaction, (ii) particle diffusion under generalized flow field, (iii) friction factor-Reynolds number equation, (iv) solid-fluid flow through ducts and (v) mixing of primary and secondary jets using the approach of Wang et al. [1] based on boundary layer concept. The extensive experimental data of several research workers along with fresh data generated on specially designed test-rig support the new approach.

In-Service Inspection Strategy for Alloy X-750 BWR Jet Pump Beams Based Upon Linear Elastic Fracture Mechanics Analysis

2009 ◽  
Author(s):  
Daniel V. Sommerville ◽  
Hardayal Mehta ◽  
Robert Carter ◽  
Jonathon Kubiak
Keyword(s):  
Fracture Mechanics ◽  
Pump Beam ◽  
Operating Experience ◽  
Linear Elastic Fracture Mechanics ◽  
Jet Pump ◽  
Linear Elastic ◽  
Flaw Tolerance ◽  
Beam Design ◽  
Jet Pumps ◽  
Elastic Fracture

Jet pumps in a boiling water reactor (BWR) are located in the annulus region between the core shroud and the reactor vessel wall and provide core flow to control reactor power. Between 16 and 24 jet pumps are included in BWR/3 through BWR/6 plants, depending on the plant rating. The inlet mixer assembly of the jet pump is secured in place with a hold down mechanism called a jet pump beam. This beam is fabricated of alloy X-750 and tensioned to 58–74% of the yield stress of the material, depending on the beam design. In recent years, more attention has been placed upon inter-granular stress corrosion cracking (IGSCC) of alloy X-750 BWR internal components as a result of in-service cracking and failures. BWR plant owners have implemented actions to manage IGSCC of jet pump beams and assemblies through increased inspections and changes to process specifications for X-750. However, a thorough understanding of the flaw tolerance of the jet pump beam was not available to guide the periodicity of inspections as well as to define critical flaw sizes needed to validate the capability of inspection techniques. This paper describes a linear elastic fracture mechanics (LEFM) evaluation in which the flaw tolerance of the existing jet pump beam designs is established and used to recommend inspection frequencies for the jet pump beam. Industry operating experience is used to assess the credibility of the results obtained from this evaluation. This work illustrates an example of the use of LEFM to develop a technically defensible basis for the required inspection regions and the frequency of inspection for an alloy X-750 BWR internal component and helps to establish the necessary sensitivity of non-destructive examination technology to be used to examine the component.

CFD Investigation of Global Performance and Three Dimensional Flows in a Water-Jet Axial Flow Pump

2005 ◽  
Author(s):  
Hong Gao ◽  
Wanlai Lin ◽  
Fangming Ye
Keyword(s):  
Three Dimensional ◽  
Axial Flow ◽  
Flow Fields ◽  
Water Jet ◽  
Jet Pump ◽  
Wall Functions ◽  
Global Performance ◽  
Jet Pumps ◽  
Axial Flow Pump ◽  
Radial Loading

The purpose of the present study is to investigate the global performance and three dimensional flow fields in a water-jet pump. TASCflow software is employed to simulate the rotator-stator coupling flow field. A standard k-ε turbulence model combined with standard wall functions is used. In order to investigate the effect of a rear stator on flow fields, the flows in two water-jet pumps with and without a rear stator are studied. The CFD predicted global performances are in good agreement with the experimental results. Then the flow fields, such as the pressure distribution on the blade surfaces, the axial and tangential velocities distribution, especially the radial loading distribution are investigated at different flow rates. In addition, the effect of a rear stator and different spacing between the rotor and the stator on the global performance and the flow fields of the water-jet pump are also investigated.

A study on Improvement of Jet-Pump Performance : Effect of Nozzle Shape

2004 ◽  
Vol 2004.53 (0) ◽  
pp. 357-358
Author(s):  
Atsushi YAMAZAKI ◽  
Tomonori NAKAYAMA ◽  
Tadashi NARABAYASI ◽  
Junya SUZUKI ◽  
Toshihiko SHAKOUCHI ◽  
...  
Keyword(s):  
Jet Pump ◽  
Performance Effect ◽  
Pump Performance ◽  
Nozzle Shape

scholarly journals Prediction of Vibration Behavior of Micro-Circular Disks at Low Reynolds Number Regime

2018 ◽  
Vol 09 (04) ◽  
pp. 1850005 ◽  
Author(s):  
Adil El Baroudi ◽  
Fulgence Razafimahery
Keyword(s):  
Analytical Procedure ◽  
Outer Boundary ◽  
Theoretical Method ◽  
Gap Effect ◽  
Governing Equations ◽  
Structure Interaction ◽  
Finite Element Software ◽  
Wide Range ◽  
Circular Disks ◽  
Good Agreement

In the current study, a theoretical method is developed to predict the vibrational behavior of micro-circular disks filled with viscous fluids and numerical results are presented to validate the model. Vibrations with two outer boundary conditions, rigid and deformable vessel, are studied. The coupled governing equations of both rigid and deformable vessel vibration are solved by the analytical procedure, taking fluid–structure interaction into account. The fluid gap effect on the coupled eigenfrequencies is also considered. The frequency spectrum plots of the first several eigenfrequencies are presented in a wide range of fluid gap and elasticity ratio. The correctness of results is demonstrated using a commercial finite element software. It is shown that the obtained results through the proposed method reveal very good agreement with the numerical solution.

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