Steady-state simulation of core-annulus flow in a circulating fluidized bed (CFB) riser

Abstract A steady-state multiphase CFD model is proposed for the simulation of core-annulus flow in a circulating fluidized bed (CFB) riser. A CFD model based on Eulerian–Eulerian approach is developed, which incorporates two mechanisms that result in the lateral profiles of solids: mixing of individual particles based on a kinetic theory treatment and mixing of clusters based on a modified k − e turbulence model. The steady-state model can simulate the core-annulus flow more efficiently, which can eliminate the unrealistic sensitivity and need less computational resources comparing with other transient models. This model shows more potential for the simulation of commercial fluidized equipments. The sensitivity of the model predictions involving four parameters indicates that e w and φ have weak influence on the correctly prediction of core-annulus flow, while the model remains a certain of sensitivity to e s and C s . The results predicted by the model show good agreement with experimental data under different operating conditions reported by Tartan and Gidaspow (2004) .

[1]  J.A.M. Kuipers,et al.  Two-fluid modeling of Geldart A particles in gas-fluidized beds , 2008 .

[2]  A. Neri,et al.  Riser hydrodynamics: Simulation using kinetic theory , 2000 .

[3]  R. Jackson,et al.  Frictional–collisional constitutive relations for granular materials, with application to plane shearing , 1987, Journal of Fluid Mechanics.

[4]  Wenyi Lin,et al.  Simulation of particle-fluid turbulence interaction in sudden-expansion flows , 1997 .

[5]  Jennifer L. Sinclair,et al.  Quantitative predictions of gas-particle flow in a vertical pipe with particle-particle interactions , 1995 .

[6]  De-Pan Shi,et al.  Three-dimensional CFD model of the temperature field for a pilot-plant tubular loop polymerization reactor , 2010 .

[7]  Wei Ge,et al.  Simulation of Heterogeneous Structure in a Circulating Fluidized-Bed Riser by Combining the Two-Fluid Model with the EMMS Approach , 2004 .

[8]  Yassir Makkawi,et al.  A model for gas–solid flow in a horizontal duct with a smooth merge of rapid–intermediate–dense flows , 2006 .

[9]  Berend van Wachem,et al.  Numerical simulation and validation of dilute turbulent gas–particle flow with inelastic collisions and turbulence modulation , 2008 .

[10]  S. Patankar.  Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[11]  L. Zhou,et al.  A two-scale second-order moment particle turbulence model and simulation of dense gas–particle flows in a riser , 2006 .

[12]  William J. Koves,et al.  Kinetic theory based CFD simulation of turbulent fluidization of FCC particles in a riser , 2006 .

[13]  V. Swaaij,et al.  Hydrodynamic modeling of dense gas-fluidised beds using the kinetic theory of granular flow: effect of coefficient of restitution on bed dynamics , 2000 .

[14]  R. Jackson,et al.  Gas‐particle flow in a vertical pipe with particle‐particle interactions , 1989 .

[15]  Dimitri Gidaspow,et al.  Measurement of Two Kinds of Granular Temperatures, Stresses, and Dispersion in Bubbling Beds , 2005 .

[16]  Tron Solberg,et al.  An experimental and computational study of multiphase flow behavior in a circulating fluidized bed , 2000 .

[17]  Sankaran Sundaresan,et al.  Gas‐solid flow in vertical tubes , 1991 .

[18]  Vivek V. Ranade,et al.  Single jet fluidized beds: Experiments and CFD simulations with glass and polypropylene particles , 2007 .

[19]  Christine M. Hrenya,et al.  Effects of particle‐phase turbulence in gas‐solid flows , 1997 .

[20]  Goodarz Ahmadi,et al.  GAS-PARTICLE TWO-PHASE TURBULENT FLOW IN A VERTICAL DUCT , 1995 .

[21]  D. Gidaspow.  Multiphase Flow and Fluidization: Continuum and Kinetic Theory Descriptions , 1994 .

[22]  Yong Jin,et al.  Modeling the hydrodynamics of downer reactors based on kinetic theory , 1999 .

[23]  S. Sundaresan,et al.  The role of meso-scale structures in rapid gas–solid flows , 2001, Journal of Fluid Mechanics.

[24]  Lixing Zhou,et al.  Theory and numerical modeling of turbulent gas-particle flows and combustion , 1993 .

[25]  Hsiaotao Bi,et al.  Hydrodynamics of turbulent fluidized beds of different diameters , 2004 .

[26]  William J. Koves,et al.  Circulation of Geldart D type particles: Part I – High solids fluxes. Measurements and computation under solids slugging conditions , 2011 .

[27]  Dimitri Gidaspow,et al.  Measurement of granular temperature and stresses in risers , 2004 .

[28]  Sofiane Benyahia.  A time-averaged model for gas–solids flow in a one-dimensional vertical channel , 2008 .

[29]  Yong Jin,et al.  Numerical simulation of the gas-particle turbulent flow in riser reactor based on k-ε-kp-εp-Θ two-fluid model , 2001 .

[30]  Botao Peng,et al.  A New Approach To Specify the Inlet Boundary Conditions for Computational Fluid Dynamics (CFD) Modeling of Hydrodynamic Behavior of a Circulating Fluidized Bed (CFB) Riser , 2012 .

[31]  Michel Y. Louge,et al.  Measurements of the collision properties of small spheres , 1994 .

[32]  Donald L. Koch,et al.  Kinetic theory for a monodisperse gas–solid suspension , 1990 .

[33]  Olivier Simonin,et al.  Granular pressure and particle velocity fluctuations prediction in liquid fluidized beds , 2008 .

[34]  H. Arastoopour,et al.  Simulation of particles and gas flow behavior in the riser section of a circulating fluidized bed using the kinetic theory approach for the particulate phase , 2000 .

[35]  Madhava Syamlal,et al.  Study of the ability of multiphase continuum models to predict core-annulus flow† , 2007 .

[36]  P. Mills,et al.  Hydrodynamic simulation of gas–solids downflow reactors , 2008 .

[37]  Sankaran Sundaresan,et al.  Turbulent gas‐particle flow in vertical risers , 1994 .

[38]  Jennifer S. Curtis,et al.  Effect of Interstitial Fluid on Particle-Particle Interactions in Kinetic Theory Approach of Dilute Turbulent Fluid-Particle Flow , 2004 .