Simulation of Granular Transport of Geldart Type-A, -B, and -D Particles through a 90° Elbow

The flow behavior of three different classes of granular materials - pulverized coal particles (type-A), glass beads (type-B), and polypropylene beads (type-D) - is numerically investigated based on computational fluid dynamics. Three elbow geometries - square and circular (R/D = 1.5 and 3.0) - are employed to investigate turbulent gas-particulate flow in dilute and dilute-to-dense phase modes of pneumatic conveying. The unsteady Eulerian-Discrete phase approach with renormalized group (RNG) k-e model is adopted, with the effects of particulate phase velocity on the gas flow, turbulent dispersion, lift forces, and particle-wall collisions incorporated in the model. The phenomenon of particle roping is well captured by the computations. Significant phase separation and particle segregation are observed in the vicinity of the lower wall of the pipe. Different classes of particles exhibit very distinct flow dynamics in terms of particle roping, particle segregation, turbulent dispersion, and particle velocit...

[1]  O. Molerus,et al.  Overview: Pneumatic transport of solids , 1996 .

[2]  Kenneth C. Williams,et al.  Predicting the mode of flow in pneumatic conveying systems—A review ☆ , 2008 .

[3]  Yutaka Tsuji,et al.  Lagrangian numerical simulation of plug flow of cohesionless particles in a horizontal pipe , 1992 .

[4]  W. Uijttewaal,et al.  Particle dispersion and deposition in direct numerical and large eddy simulations of vertical pipe flows , 1996 .

[5]  M. Sommerfeld,et al.  EXPERIMENTAL STUDIES AND MODELLING OF FOUR-WAY COUPLING IN PARTICLE-LADEN HORIZONTAL CHANNEL FLOW , 2002, Proceeding of Second Symposium on Turbulence and Shear Flow Phenomena.

[6]  Edward K. Levy,et al.  Investigation of gas–solid flow structure after a 90° vertical-to-horizontal elbow for low conveying gas velocities , 2005 .

[7]  Kelvin Chu,et al.  Numerical simulation of complex particle-fluid flows , 2006 .

[8]  Martin Sommerfeld,et al.  Modelling and numerical calculation of dilute-phase pneumatic conveying in pipe systems , 1998 .

[9]  Aibing Yu,et al.  Numerical simulation of the gas-solid flow in a fluidized bed by combining discrete particle method with computational fluid dynamics , 1997 .

[10]  Pertti Sarkomaa,et al.  An experimental study of vertical pneumatic conveying , 1999 .

[11]  Clayton T. Crowe,et al.  Numerical models for two-phase turbulent flows , 1996 .

[12]  W. Tabakoff,et al.  Laser Measurements of Fly Ash Rebound Parameters for Use in Trajectory Calculations , 1985 .

[13]  Yuji Tomita,et al.  WAVELIKE MOTION OF PARTICULATE SLUGS IN A HORIZONTAL PNEUMATIC PIPELINE , 1981 .

[14]  Jun Yao,et al.  Antierosion in a 90° bend by particle impaction , 2002 .

[15]  Avi Levy,et al.  The effect of a bend on the particle cross-section concentration and segregation in pneumatic conveying systems , 1998 .

[16]  Martin Sommerfeld,et al.  Characterization of the cross-sectional particle concentration distribution in pneumatic conveying systems , 1994 .

[17]  Madhumita B. Ray,et al.  Pneumatic transport of granular materials through a 90° bend , 2004 .

[18]  Anders Rasmuson,et al.  Some aspects on gas–solid flow in a U-bend: Numerical investigation , 2005 .

[19]  Peter W Wypych,et al.  Pressure drop and slug velocity in low-velocity pneumatic conveying of bulk solids , 1997 .

[20]  R. Mei.  An approximate expression for the shear lift force on a spherical particle at finite reynolds number , 1992 .

[21]  Edward K. Levy,et al.  Formation and dispersion of ropes in pneumatic conveying , 2001 .

[22]  Tomasz Dyakowski,et al.  Applications of electrical tomography for gas-solids and liquid-solids flows : a review , 2000 .

[23]  Harun Bilirgen,et al.  Mixing and dispersion of particle ropes in lean phase pneumatic conveying , 2001 .

[24]  H. P. Simons,et al.  Flow characteristics in horizontal fluidized solids transport , 1959 .

[25]  John R. Pugh,et al.  Bend Pressure Drop Predictions Using the Euler-Euler Model in Dense Phase Pneumatic Conveying , 2007 .

[26]  William Yang,et al.  Experimental investigation of dilute turbulent particulate flow inside a curved 90° bend , 2006 .

[27]  C. Crowe,et al.  The Particle-Source-In Cell (PSI-CELL) Model for Gas-Droplet Flows , 1977 .

[28]  Jiemin Zhou,et al.  Numerical study on pressure prediction and its main influence factors in pneumatic conveyors , 2010 .

[29]  Ian Lowndes,et al.  Characterisation of the cross sectional particle concentration distribution in horizontal dilute flow conveying—a review , 2004 .

[30]  Aibing Yu,et al.  Particle-scale modelling of gas-solid flow in fluidisation † , 2003 .

[31]  D. Geldart.  Types of gas fluidization , 1973 .

[32]  Ming Yin,et al.  Renormalization group based κ − ε turbulence model for flows in a duct with strong curvature , 1996 .

[33]  Edward K. Levy,et al.  Gas–solid flow behavior in a horizontal pipe after a 90° vertical-to-horizontal elbow , 2001 .

[34]  Benny Kuan,et al.  Dilute gas–solid two-phase flows in a curved 90∘ duct bend: CFD simulation with experimental validation , 2007 .

[35]  Clayton T. Crowe,et al.  Review—Numerical Models for Dilute Gas-Particle Flows , 1982 .

[36]  Sankaran Sundaresan,et al.  Electrical capacitance tomography measurements on vertical and inclined pneumatic conveying of granular solids , 2003 .

[37]  Hidesato Ito,et al.  Flow in curved pipes. , 1987 .

[38]  S. Laouar,et al.  Experimental characterization of the pressure drop in dense phase pneumatic transport at very low velocity , 1998 .