vii
TABLE OF CONTENTS
CHAPTER
1
TITLE
PAGE
TITLE
i
DECLARATION
ii
DEDICATION
iii
ACKNOWLEDGEMENTS
iv
ABSTRACT
v
ABSTRAK
vi
CONTENTS
vii
LIST OF FIGURES
xi
LIST OF ABBREVIATIONS
xiv
LIST OF APPENDICES
xv
INTRODUCTION
1.1
Process Tomography
1
1.2
Project background
3
1.3
Problem Statements
4
1.4
Objective of the project
6
1.5
Scope of work
6
1.6
The Thesis Outline
7
viii
2
LITERATURE REVIEW
2.1
An Overview of process Tomography
9
2.2
Tomography Sensors
10
2.2.1
11
2.2.2 Electrical Resistance Tomography (ERT)
13
2.2.3
Electrical Impedance Tomography (EIT)
14
2.2.4
Ultrasonic Tomography
15
2.2.5
X-ray tomography
15
2.2.6
Optical Tomography
16
2.2.7
Electrical Charge Tomography
17
2.3
Application of Process Tomography
19
2.4
Optical Projection
22
2.5
Fiber Optics
24
2.5.1 Single-mode fibre
26
2.5.2 Multimode fibres
27
2.5.3
27
2.6
3
Electrical Capacitance Tomography (ECT)
Fiber Optics Applications
Particles Charging Mechanism
29
HARDWARE DESIGN
3.1
Introduction
30
3.2
Pipe Design
30
3.3
Optical Tomography System
32
3.3.1
Selection of Optical Sensor
34
3.3.2
Light Source
36
3.3.3
Signal Conditioning Circuit
37
3.3.3.1 Current to Voltage Circuit Converter
38
ix
3.3.3.2
3.4
First and Second Stage Amplifier
Electrodynamic Tomography System
41
3.4.1
Electrodynamic Sensor
43
3.4.2
Signal conditioning circuit for
electrodynamic
sensor
4
44
3.5
The Data Acquisition System
48
3.6
Complete Hardware Design
50
SOFTWARE DESIGN
4.1
Introduction
51
4.2
Concentration Profile
51
4.3
Linear Back Projection Technique
52
4.4
Sensitivity Maps
54
4.4.1
Optical Sensitivity Maps
54
4.4.2
Electrodynamic Sensitivity Maps
56
4. 5
5
39
Programming Structure
59
RESULTS
5.1
Introduction
60
5.2
Circuit Testing
61
5.3
Concentration Profile from the Offline Data
65
5.3.1 Concentration Profile during No-Flow
Condition
66
5.3.2 Concentration Profile during Full-flow
Condition
67
x
5.3.3 Concentration Profile during Object at the
middle
68
5.3.4 Concentration Profile during 20mm PVC Pipe
6
dropped close to the Pipe wall
69
5.3.5 Concentration Profile during transparent rod
70
5.3.6 Concentration Profile during Two Objects Flow
71
CONCLUSION AND FUTURE RECOMMENDATION
6.1
Conclusion
73
6.2
Suggestions for Future Works
75
REFERENCES
76
Appendices A-E
79-133
LIST OF FIGURES
FIGURE
DESCRIBTION
PAGE
2.1
Overview of process tomography
10
2.2
ECT measurement circuits
12
2.3
Diagram showing the electrical model of EIT
14
2.4(a)
Orthogonal type parallel projections
23
2.4(b)
Rectilinear type parallel projections
23
2.4(c)
Combination of orthogonal and rectilinear projections
23
2.4(d)
Three fan beam projections
23
2.4(e)
Four fan-beam projections
24
2.5
Single and multimode fibers
25
2.6
Types of fiber propagation and dispersion
26
3.1
Pipe design
31
3.2
Optical Imaging System
32
3.3
Fiber optics arrangement
33
3.4
BPX65 photodiode
35
3.5
MR16 halogen lamp
37
3.6
Schematic circuit of receiver
38
3.7
Current to Voltage Converter
38
3.8
Buffer
40
3.9
Third stage signal amplifier
40
3.10
The optical imaging system being tested
41
3.11
An array of sensors in clockwise order
42
3.12
Block diagram of an electrical charge sensing system
44
3.13
A photo of the electrodynamics circuits
45
3.14
Non-inverting voltage follower
46
xii
3.15
Non-inverting voltage amplifier
47
3.16
Connection of sensors to the PC
49
3.17
The complete hardware system.
50
4.1
Back projection
53
4.2
Theoretical concentration matrix tomogram. (a) 2D view and
(b) 3D view
54
4.3(a-d)
Sensitivity maps for an 8 sensors
55
4.3(e-h)
Sensitivity maps for an 8 sensors
56
4.4
The pipe co-ordinates model
57
4.5
Sensitivity map of sensor 1
57
4.6
3D sensitivity map of sensor 1
58
5.1(a)
Output 1
61
5.1(a-b)
Output 2 and Output 3
62
5.2
Average output using hand touch
63
5.3
The hand is fixed at the electrode for period of time
63
5.4
Output signal when the sensor receiving surrounding lights
64
5.5
Optical output when the light not blocked
64
5.6
The optical output when light is blocked
65
5.7
The concentration profile for the no-flow condition (a) Obtained
from electrodynamic system and (b) Obtained from optical system
5.8
The concentration profile for the full-flow condition (a) Obtained
from electrodynamic system and (b) Obtained from optical system
5.9
66
67
The concentration profile when the square wood bar is inserted at
the middle (a) Obtained from electrodynamic system and (b)
Obtained from optical system
5.10
68
The concentration profile when the 20mm PVC pipe is inserted
close to wall of the pipe (a) Obtained from optical system and (b)
Obtained from electrodynamic system
5.11
69
The concentration profile for transparent rod (a) Obtained from
electrodynamic system and (b) Obtained from optical system
70
xiii
5.12
The concentration profile for the two objects (a) Obtained from
optical system (b) Obtained from electrodynamic system
72
xiv
LIST OF ABBREVIATIONS
A
-
Area of the capacitor plate
AC
-
Alternating Current
C
-
Capacitance
dp
-
Distance Between Two Plates
DAS
-
Data Acquisition System
DC
-
Direct Current
ECT
-
Electrical Capacitance Tomography
EIT
-
Electrical Impedance Tomography
ERT
-
Electrical Resistance Tomography
LBP
-
Linear Back Projection
NMR
-
Nuclear Magnetic Resonance
PC
-
Personal Computer
PET
-
Positron Emission Tomography
PVC
-
Polyvinyl Cloride
Q
-
Quantity of charge in coulombs
Rf
-
Feedback resistance
V
-
Voltage in volts
τ
-
Time constant
ε0
-
Permittivity Of Free Space
εr
-
Permittivity Of The Dielectric
xv
LIST OF APPENDICES
APPENDIX
A
TITLE
Schematic Diagram for the Electrodynamic Transducer
Circuit
B
Data Sheet for TL084A
C
Data Sheet for LF351
D
Data Sheet for BPX65 Series
E
Software Program
PAGE