Chapter 1
Background
Chapter
2 Literature Survey
2.1
Introduction
2.2
Complex pipe systems
2.2.1
Industrial scale circulating fluidized bed (CFB)
2.2.2
Long-distance high-pressure dense-phase (LHD) pneumatic conveying system
2.2.3
Bypass pneumatic conveying system
2.3 Numerical
methods
2.3.1 Two
fluid model (TFM)
2.3.2
Discrete element method (DEM)
2.3.3
Coupling of DEM and CFD
2.3.4
Coarse-grained (CG) /parcel CFD-DEM approach
2.4
Summary and proposed research
Chapter
3 Simulation of Industrial Scale CFB Using Coarse Grained CFD-DEM Model
3.1
Introduction
3.2
Experiments and simulation conditions
3.2.1
Backgrounds
3.2.2
Experimental set up and measurements
3.2.3
Mathematical model
3.2.4
Simulation conditions
3.3 Results
and discussion
3.3.1
Axia] pressure gradient
3.3.2
Solid velocity and concentration
3.3.3
Particle cluster and solids back mixing
3.3.4
Analysis of the interaction forces
3.3.5 Effects
of different model particle sizes
3.3.6 Effects
of different solid mass flow rate
3.4
Conclusions
Chapter 4
Computational Study of Gas-solid Flow in LHD Pneumatic Conveying Systems
4.1
Introduction
4.2
Mathematical model
4.2.1
TFM
4.2.2
CFD-DEM
4.3
Simulation conditions
4.4 Model
validation
4.5
Results and discussion
4.5.1
Pressure drop
4.5.2
Gas velocity
4.5.3
Solid velocity
4.5.4
Forces governing the motion of solids
4.6
Conclusion2
Chapter 5
Numerical Study of Gas-solid Flow in Stepped Pipe with Inserts
5.1
Introduction
5.2
Mathematical model
5.2.1
TFM
5.2.2 CFD-DEM
5.3
Simulation conditions
5.4 Results
and discussion
5.4.1
Single pipe with inserts
5.4.2 Stepped
pipe with inserts
5.4.3
Different shape of inserts
5.5
Conclusions
Chapter 6
Particle-scale Modelling of Gas-solid Flow in Bypass System
6.1
Introduction
6.2
Mathematical model
6.3
Simulation conditions
6.4 Results
and discussion
6.4.1
Grid study
6.4.2
Pressure drop
6.4.3
Gas velocity
6.4.4
Solid velocity and general flow pattern
6.4.5
Forces governing particle motion
6.5
Conclusions
Chapter 7
Effects Geometrical Parameters on the Gas-solid Flow in Bypass System
7.1
Introduction
7.2
Simulation method
7.3
Simulation conditions
7.4 Results
and discussion
7.4.1
Effect of flute spacing
7.4.2
Effect of small internal pipe diameters
7.4.3 Effect
of orifice path diameter
7.5
Conclusions
Chapter 8
Summary and Future Work
8.1
Summary
8.2
Future work
References