This book is for engineers and students to solve issues concerning the fluidized bed systems. It presents an analysis that focuses directly on the problem of predicting the fluid dynamic behavior which empirical data is limited or unavailable. The second objective is to provide a treatment of computational fluidization dynamics that is readily accessible to the non-specialist. The approach adopted in this book, starting with the formulation of predictive expressions for the basic conservation equations for mass and momentum using kinetic theory of granular flow. The analyses presented in this book represent a body of simulations and experiments research that has appeared in numerous publications over the last 20 years. This material helps to form the basis for university course modules in engineering and applied science at undergraduate and graduate level, as well as focused, post-experienced courses for the process, and allied industries.
Author(s): Huilin Lu, Dimitri Gidaspow, Shuyan Wang
Publisher: Springer
Year: 2021
Language: English
Pages: 209
City: Singapore
Preface
Contents
1 Introduction to Fluidization Basic Equations
1.1 Introduction
1.2 Conservations Laws for Fluidization
1.2.1 Mass Balances
1.2.2 Momentum Balances
1.2.3 Energy Balances
1.2.4 Conservation of Species
References
2 Constitutive Equations with Kinetic Theory of Granular Flow
2.1 Introduction
2.2 Elementary Kinetic Theory
2.2.1 Dynamics of an Encounter Between Two Particles
2.2.2 Peculiar Velocity and Transport
2.2.3 Granular Temperature and the Equation of State
2.3 Frequency of Collisions
2.4 Boltzmann Integral—Differential Equation
2.5 Kinetic Theory of Granular Flow
2.5.1 Maxwell’s Transport Equation
2.5.2 Constitutive Correlations
2.6 Kinetic-Frictional Stress Models
2.7 Boundary Conditions
2.8 Kinetic Theory of Particles Mixture
2.8.1 Boltzmann Equations for PhaseI in a Mixture of M Phases
2.8.2 Dense Transport Theorem
2.8.3 Conservation Equations
2.8.4 Constitutive Equations
2.8.5 Summary of Model Equations
References
3 Homogeneous and Nonhomogeneous Interfacial Momentum Closure
3.1 Introduction
3.2 Governing Equations of Gas-Particles KTGF-Based TFM Model
3.3 Homogeneousfluid-Particle Drag
3.3.1 Gidaspow Drag Coefficient Model
3.3.2 Huilin-Gidaspow Drag Coefficient Model
3.3.3 Syamlal and O'Brien Drag Coefficient Model
3.3.4 Gibilaro Drag Coefficient Model
3.4 Filtered or Subgrid Model
3.5 Energy Minimization Multi-scale (EMMS) Model
3.6 Dynamic Cluster Structure-Dependent Drag Model
3.6.1 Heterogeneous Flow with Dilute Phase and Dense Phase
3.6.2 Criterion for Identification of Clusters
3.6.3 Dynamic Cluster Structure-Dependent (DCSD) Drag Model
3.6.4 Transient Equations of Dilute Phase and Dense Phase
3.6.5 Conditioned Extreme Value Equation Based on BEV Theory
3.6.6 Minimization of Energy Dissipation Rate of Heterogeneous Structure
3.6.7 Intermittency of Heterogeneous Structures
3.6.8 Compromise of Energy Dissipations Between Gas-Particles and Inter-Particle Interactions
3.6.9 Predicted Cluster Properties from DCSD Drag Model
References
4 Experimental Foundation
4.1 Introduction
4.2 Solids Volume Fractions Measurements
4.2.1 Radial Solids Volume Fractions and Density
4.2.2 Solids Volume Fractions of Bubbling Fluidized Bed
4.3 Measured Particles Velocities and Granular Temperature
4.3.1 Velocity Measurements of Particles
4.3.2 Granular Temperature of Particles
4.4 Radial Distribution Function Measurement
4.5 Particle-Pressure Transducer and Measured Particle Pressure
4.6 FCC Equation of State
4.7 Solids Viscosity Measurements
4.8 Experiments of Extracting Alumina from Coal Fly Ash in Fluidized Bed
4.8.1 Experimental Processes
4.8.2 Experimental Alumina Extraction Efficiency
References
5 Tutorial for Numerical Methods and Program Solution Technique
5.1 Conservation Laws and Convection Diffusion
5.1.1 Nonconservative Form
5.1.2 Conservative Upwind (Donor Cell) Form
5.1.3 Other Conservative Forms
5.1.4 Upwinding
5.2 Numerical Diffusion
5.3 Optimum Time Step
5.4 Flux-Corrected Transport
5.5 Staggered Mesh Differencing and the ICE Method
5.5.1 Computational Grid
5.5.2 Differencing Technique for Mass and Momentum
5.5.3 Overview of Solution Technique Using a Residue
5.5.4 The Finite Difference Equations and Averaging Process
5.5.5 Solution Technique for Finite-Difference Equations
5.6 Boundary Conditions
5.6.1 Wall Boundary Conditions
5.6.2 Inflow Boundary Cells
5.6.3 Outflow Boundary Cells
5.6.4 Initial Conditions
5.6.5 Tips for Running the CFD Code
References
6 Cases for Numerical Simulations of Fluidized Bed Systems
6.1 Fluidized Bed Coal Combustors
6.1.1 Circulating Fluidized Bed (CFB) Coal Combustors
6.1.2 Hybrid Pulverized-Fluidized Bed Coal Combustors
6.2 Fluidized Bed Chemical-Looping Processes
6.2.1 Diameter Transformed Fluidized Bed Chemical-Looping Combustion (CLC)
6.2.2 Circulating Fluidized Bed Chemical-Looping Combustion
6.2.3 Dual Circulating Fluidized Bed Chemical-Looping Combustion
6.2.4 Fluidized Bed Chemical Looping Reforming (CLR)
6.3 Fluidized Bed CO2 Capture
6.4 Supercritical Water Fluidized Bed (SCWFB) of Binary Mixture
References
