The Experts below are selected from a list of 6396 Experts worldwide ranked by ideXlab platform

Hao Zhang - One of the best experts on this subject based on the ideXlab platform.

  • numerical investigation of the location of maximum erosive wear damage in elbow effect of slurry velocity bend orientation and angle of elbow
    Powder Technology, 2012
    Co-Authors: Yong Sheng, Dongmin Yang, Shengqiang Jiang, Hao Zhang, F X Trias, A Oliva
    Abstract:

    Abstract A numerical simulation of fluid transportation process was carried out focused on the investigation into predicting the location of the puncture point location in elbow. The kinematics and trajectory of the discrete particles as well as the particle–particle Interaction were described by discrete element method (DEM) while the hydrodynamic model of the fluid phase was based on the volume-averaged Navier–Stokes equations, and a fluid density-based buoyancy model was adopted to calculate the solid–fluid Interaction force. In this paper, the spatial distribution of particle–wall Interaction force was calculated and corresponded to the wear pattern in the elbow, the puncture point locations have been observed. In particular, the influences of slurry velocity, bend orientation and angle of elbow on the puncture point location were discussed.

  • Numerical simulation of concrete pumping process and investigation of wear mechanism of the piping wall
    Tribology International, 2012
    Co-Authors: Yuanqiang Tan, Dongmin Yang, Junhua Song, Shengqiang Jiang, Hao Zhang, Yong Sheng
    Abstract:

    A numerical simulation has been conducted to study the solid-fluid multi-phase flow problem in concrete pumping process. The kinematics and trajectory of the discrete particles as well as the Particle-Particle Interaction were predicted by DEM while the motion of the continuous fluid phase was evaluated by a Navier-Stokes solver, and a pressure gradient force model was adopted to calculate the solid-fluid Interaction force. A case of pneumatic conveying was utilized to demonstrate the capability of the coupling model. The concrete pumping process was then simulated, where several flow features were observed such as roping, particle segregation and particle concentration. The frequency of the particles impacting on the bended pipe was monitored, a new time average collision intensity model based on impact force has been proposed to investigate the wear mechanism of the elbow. The location of maximum erosive wear damage in the elbow was predicted. Statistical results were in good agreement with that observed in actual pumping process. It is found that the present multi-phase coupling model can predict the wear behavior of the bended pipe accurately, and consequently provide an effective guidance for the design of concrete pumping pipe. © 2011 Elsevier Ltd.

Yong Sheng - One of the best experts on this subject based on the ideXlab platform.

  • numerical investigation of the location of maximum erosive wear damage in elbow effect of slurry velocity bend orientation and angle of elbow
    Powder Technology, 2012
    Co-Authors: Yong Sheng, Dongmin Yang, Shengqiang Jiang, Hao Zhang, F X Trias, A Oliva
    Abstract:

    Abstract A numerical simulation of fluid transportation process was carried out focused on the investigation into predicting the location of the puncture point location in elbow. The kinematics and trajectory of the discrete particles as well as the particle–particle Interaction were described by discrete element method (DEM) while the hydrodynamic model of the fluid phase was based on the volume-averaged Navier–Stokes equations, and a fluid density-based buoyancy model was adopted to calculate the solid–fluid Interaction force. In this paper, the spatial distribution of particle–wall Interaction force was calculated and corresponded to the wear pattern in the elbow, the puncture point locations have been observed. In particular, the influences of slurry velocity, bend orientation and angle of elbow on the puncture point location were discussed.

  • Numerical simulation of concrete pumping process and investigation of wear mechanism of the piping wall
    Tribology International, 2012
    Co-Authors: Yuanqiang Tan, Dongmin Yang, Junhua Song, Shengqiang Jiang, Hao Zhang, Yong Sheng
    Abstract:

    A numerical simulation has been conducted to study the solid-fluid multi-phase flow problem in concrete pumping process. The kinematics and trajectory of the discrete particles as well as the Particle-Particle Interaction were predicted by DEM while the motion of the continuous fluid phase was evaluated by a Navier-Stokes solver, and a pressure gradient force model was adopted to calculate the solid-fluid Interaction force. A case of pneumatic conveying was utilized to demonstrate the capability of the coupling model. The concrete pumping process was then simulated, where several flow features were observed such as roping, particle segregation and particle concentration. The frequency of the particles impacting on the bended pipe was monitored, a new time average collision intensity model based on impact force has been proposed to investigate the wear mechanism of the elbow. The location of maximum erosive wear damage in the elbow was predicted. Statistical results were in good agreement with that observed in actual pumping process. It is found that the present multi-phase coupling model can predict the wear behavior of the bended pipe accurately, and consequently provide an effective guidance for the design of concrete pumping pipe. © 2011 Elsevier Ltd.

Michael Fairweather - One of the best experts on this subject based on the ideXlab platform.

  • Fine particle turbulence modulation
    AIChE Journal, 2011
    Co-Authors: David Harbottle, Simon Biggs, Michael Fairweather
    Abstract:

    Streamwise turbulence intensities of fine particulate suspensions were studied in a 26 mm N.B. horizontal pipe loop. Colloidal silica spheres were prepared in 10(-4) M and 1M KNO(3) solutions to control the degree of aggregate formation in the suspension. Using an ultrasonic Doppler velocity profiling sensor, the turbulence intensities of the fine particle suspensions were compared with those of a particle-free flow over a range of Reynolds numbers. At low electrolyte concentration, the silica particles remain dispersed, with the turbulence intensity of the suspension flow comparable with that of the particle-free flow. At high electrolyte concentration, increased Particle-Particle Interaction leads to the formation of particle aggregates which support turbulence augmentation over a critical Reynolds number range. The range of Reynolds numbers over which this turbulence enhancement is observed is limited by both fluid dynamic effects at low Reynolds numbers (Re approximate to 5500) and aggregate breakup at high Reynolds numbers (Re approximate to 8000). (C) 2010 American Institute of Chemical Engineers AIChE J, 57: 1693-1699, 2011

  • The effect of Particle-Particle Interaction forces on the flow properties of silica slurries
    11th International Conference on Environmental Remediation and Radioactive Waste Management Parts A and B, 2007
    Co-Authors: David Harbottle, Michael Fairweather, Dominic Rhodes, Simon Biggs
    Abstract:

    Preliminary work has been completed to investigate the effect of Particle-Particle Interaction forces on the flow properties of silica slurries. Classically Hydrotransport studies have focused on the flow of coarse granular material in Newtonian fluids. However, with current economical and environmental pressures, the need to increase solid loadings in pipe flow has lead to studies that examine non-Newtonian fluid dynamics. The flow characteristics of non-Newtonian slurries can be greatly influenced through controlling the solution chemistry. Here we present data on an “ideal” slurry where the particle size and shape is controlled together with the solution chemistry. We have investigated the effect of adsorbed cations on the stability of a suspension, the packing nature of a sediment and the frictional forces to be overcome during reslurrying. A significant change in the criteria assessed was observed as the electrolyte concentration was increased from 0.1mM to 1M. In relation to industrial processes, such delicate control of the slurry chemistry can greatly influence the optimum operating conditions of non-Newtonian pipe flows.Copyright © 2007 by ASME

Dongmin Yang - One of the best experts on this subject based on the ideXlab platform.

  • numerical investigation of the location of maximum erosive wear damage in elbow effect of slurry velocity bend orientation and angle of elbow
    Powder Technology, 2012
    Co-Authors: Yong Sheng, Dongmin Yang, Shengqiang Jiang, Hao Zhang, F X Trias, A Oliva
    Abstract:

    Abstract A numerical simulation of fluid transportation process was carried out focused on the investigation into predicting the location of the puncture point location in elbow. The kinematics and trajectory of the discrete particles as well as the particle–particle Interaction were described by discrete element method (DEM) while the hydrodynamic model of the fluid phase was based on the volume-averaged Navier–Stokes equations, and a fluid density-based buoyancy model was adopted to calculate the solid–fluid Interaction force. In this paper, the spatial distribution of particle–wall Interaction force was calculated and corresponded to the wear pattern in the elbow, the puncture point locations have been observed. In particular, the influences of slurry velocity, bend orientation and angle of elbow on the puncture point location were discussed.

  • Numerical simulation of concrete pumping process and investigation of wear mechanism of the piping wall
    Tribology International, 2012
    Co-Authors: Yuanqiang Tan, Dongmin Yang, Junhua Song, Shengqiang Jiang, Hao Zhang, Yong Sheng
    Abstract:

    A numerical simulation has been conducted to study the solid-fluid multi-phase flow problem in concrete pumping process. The kinematics and trajectory of the discrete particles as well as the Particle-Particle Interaction were predicted by DEM while the motion of the continuous fluid phase was evaluated by a Navier-Stokes solver, and a pressure gradient force model was adopted to calculate the solid-fluid Interaction force. A case of pneumatic conveying was utilized to demonstrate the capability of the coupling model. The concrete pumping process was then simulated, where several flow features were observed such as roping, particle segregation and particle concentration. The frequency of the particles impacting on the bended pipe was monitored, a new time average collision intensity model based on impact force has been proposed to investigate the wear mechanism of the elbow. The location of maximum erosive wear damage in the elbow was predicted. Statistical results were in good agreement with that observed in actual pumping process. It is found that the present multi-phase coupling model can predict the wear behavior of the bended pipe accurately, and consequently provide an effective guidance for the design of concrete pumping pipe. © 2011 Elsevier Ltd.

David Harbottle - One of the best experts on this subject based on the ideXlab platform.

  • Fine particle turbulence modulation
    AIChE Journal, 2011
    Co-Authors: David Harbottle, Simon Biggs, Michael Fairweather
    Abstract:

    Streamwise turbulence intensities of fine particulate suspensions were studied in a 26 mm N.B. horizontal pipe loop. Colloidal silica spheres were prepared in 10(-4) M and 1M KNO(3) solutions to control the degree of aggregate formation in the suspension. Using an ultrasonic Doppler velocity profiling sensor, the turbulence intensities of the fine particle suspensions were compared with those of a particle-free flow over a range of Reynolds numbers. At low electrolyte concentration, the silica particles remain dispersed, with the turbulence intensity of the suspension flow comparable with that of the particle-free flow. At high electrolyte concentration, increased Particle-Particle Interaction leads to the formation of particle aggregates which support turbulence augmentation over a critical Reynolds number range. The range of Reynolds numbers over which this turbulence enhancement is observed is limited by both fluid dynamic effects at low Reynolds numbers (Re approximate to 5500) and aggregate breakup at high Reynolds numbers (Re approximate to 8000). (C) 2010 American Institute of Chemical Engineers AIChE J, 57: 1693-1699, 2011

  • The effect of Particle-Particle Interaction forces on the flow properties of silica slurries
    11th International Conference on Environmental Remediation and Radioactive Waste Management Parts A and B, 2007
    Co-Authors: David Harbottle, Michael Fairweather, Dominic Rhodes, Simon Biggs
    Abstract:

    Preliminary work has been completed to investigate the effect of Particle-Particle Interaction forces on the flow properties of silica slurries. Classically Hydrotransport studies have focused on the flow of coarse granular material in Newtonian fluids. However, with current economical and environmental pressures, the need to increase solid loadings in pipe flow has lead to studies that examine non-Newtonian fluid dynamics. The flow characteristics of non-Newtonian slurries can be greatly influenced through controlling the solution chemistry. Here we present data on an “ideal” slurry where the particle size and shape is controlled together with the solution chemistry. We have investigated the effect of adsorbed cations on the stability of a suspension, the packing nature of a sediment and the frictional forces to be overcome during reslurrying. A significant change in the criteria assessed was observed as the electrolyte concentration was increased from 0.1mM to 1M. In relation to industrial processes, such delicate control of the slurry chemistry can greatly influence the optimum operating conditions of non-Newtonian pipe flows.Copyright © 2007 by ASME