vii
TABLE OF CONTENTS
CHAPTER
1
2
TITLE
PAGE
DECLARATION
ii
DEDICATION
iii
ACKNOWLEDGEMENT
iv
ABSTRACT
v
ABSTRAK
vi
TABLE OF CONTENTS
vii
LIST OF TABLES
xiii
LIST OF FIGURES
xviii
LIST OF ABBREVIATIONS
xxvii
LIST OF SYMBOLS
xxix
LIST OF APPENDICES
xxxii
INTRODUCTION
1
1.1 Background
1
1.2 Statement of problem
3
1.3 Research objectives
4
1.4 Scope of study
4
1.5 Significance of the study
6
1.6 Organisation of thesis
6
LITERATURE SURVEY
9
2.1 Introduction
9
2.1.1
Span dominated ground effect
10
2.1.2
Chord dominated ground effect
10
2.2 Literature review
11
viii
2.2.1
Aerodynamic characteristic of wing near
ground
2.2.2
11
Influence of wing configuration on
aerodynamic performance in ground effect
2.2.3
Flow separation and wake region behind wing
near ground
2.2.4
2.2.5 Optimal design of wing in ground effect
33
37
Fuel consumption and environmental impact of
craft
3
32
Aerodynamics of wing via viscous ground
effect in ground proximity
2.2.9
30
Effect of power ram engine on aerodynamic
performance of WIG craft
2.2.8
28
Aerodynamic characteristic of a multi-element
wing near ground
2.2.7
20
Aerodynamic characteristics of WIG craft on
free surface
2.2.6
18
39
METHODOLOGY
42
3.1 Introduction
42
3.2 Computational methodology
43
3.2.1 General
43
3.2.2 CFD simulation
43
3.2.2.1
Pre-processing
43
3.2.2.2
Solver
44
3.2.2.3
Post-processing
44
3.2.3 Mathematical model
45
3.2.4 Turbulent models
45
3.2.4.1
Standard k-ε turbulent model
45
3.2.4.2
k-ω SST turbulent model
49
3.2.4.3
Realizable k-ε turbulent model
50
3.2.5
Boundary layer at near-wall
51
3.2.6
Standard wall functions
53
ix
3.2.7
Pressure-Based Solver
54
3.2.8
Shape of linear formulation
56
3.2.9
Boundary conditions
57
3.2.9.1
Wall boundary condition
57
3.2.9.2
Velocity -inlet boundary condition
58
3.2.9.3
Pressure outlet boundary condition
58
3.2.9.4
Symmetry boundary conditions
59
3.2.10
Solutions controls
3.2.10.1
Discretisation
59
3.2.10.2
Under-relaxation factors
60
3.2.10.3
Pressure-Velocity Coupling Method
60
3.2.11 Meshing
61
3.2.12 Post-processing
62
3.3 Experimental methodology
63
3.3.1
Wind tunnel
63
3.3.1.1
Theory of operation
63
3.3.1.2
How does wind tunnel work?
63
3.3.2
UTM Wind tunnel
3.3.2.1
4
59
64
Introduction to UTM Wind Tunnel
facility
64
3.3.2.2
Test section
65
3.3.2.3
Fan motor and drive system
66
3.3.2.4
Settling chamber
67
3.3.2.5
Balance System
67
3.3.2.6
Facility control system
68
3.3.3
Wing Model
68
3.3.4
Experimental procedures and set-up
70
NUMERICAL AERODYNAMIC
CHARACTERISTICS OF A NEW COMPOUND
WING INTRODUCTION
73
4.1 General
73
4.2 CFD Numerical study
73
x
4.3 Validation of CFD simulation
4.3.1
Lift Coefficient (CL)
78
4.3.2
Drag Coefficient (CD)
80
4.3.3
Lift to drag ratio (L/D)
82
4.4 Result and discussion
5
78
84
4.4.1
Lift Coefficient (CL)
84
4.4.2
Drag Coefficient (CD)
86
4.4.3
Lift to drag ratio (L/D)
88
EXPERIMENTAL AERODYNAMIC
CHARACTERISTICS OF A NEW COMPOUND
WING
91
5.1 General
91
5.2 Repeatability of experiment
92
5.3 Principal aerodynamic forces of compound and
rectangular wing
92
5.3.1
Lift coefficient
93
5.3.2
Drag coefficient
94
5.3.3
Moment coefficient
95
5.4 Comparison of aerodynamic coefficients between
compound and rectangular wings
96
5.4.1
Lift coefficient
96
5.4.2
Drag coefficient
98
5.4.3
Lift to drag ratio
100
5.4.4
Drag polar
102
5.4.5
Moment coefficient
104
5.4.6
Centre of pressure
106
5.5 Tendency of numerical and experimental simulations
6
108
DESIGN PARAMETRIC STUDY OF
CONFIGURATION OF COMPOUND WING
110
6.1 General
110
6.2 CFD Numerical study
110
6.3 Validation of CFD simulation
114
xi
6.3.1
Lift Coefficient (CL)
115
6.3.2
Drag Coefficient (CD)
116
6.3.3
Lift to drag ratio (L/D)
117
6.4 Design parametric study of compound wing
6.4.1
6.4.2
Span size
118
6.4.1.1
Pressure and velocity contours
118
6.4.1.2
Lift coefficient
122
6.4.1.3
Drag coefficient
124
6.4.1.4
Lift to drag ratio
125
6.4.1.5
Moment coefficient and centre of
pressure
126
Anhedral angle (a)
129
6.4.2.1
Pressure and velocity contours
129
6.4.2.2
Lift coefficient
133
6.4.2.3
Drag coefficient
136
6.4.2.4
Lift to drag ratio
137
6.4.2.5
Moment coefficient and centre of
pressure
6.4.3
6.4.4
6.4.5
118
135
Taper ratio (λ)
139
6.4.3.1
Pressure and velocity contours
139
6.4.3.2
Lift coefficient
142
6.4.3.3
Drag coefficient
143
6.4.3.4
Lift to drag ratio
145
6.4.3.5
Moment coefficient and centre of
pressure
146
Ground clearance
148
6.4.4.1
Pressure and velocity contours
148
6.4.4.2
Lift coefficient
151
6.4.4.3
Drag coefficient
153
6.4.4.4
Lift to drag ratio
154
6.4.4.5
Moment coefficient and centre of
pressure
155
Reynolds number
158
xii
6.4.5.1
Pressure and velocity contours
158
6.4.5.2
Lift coefficient
160
6.4.5.3
Drag coefficient
162
6.4.5.4
Lift to drag ratio
163
6.4.5.5
Moment coefficient and centre of
pressure
6.4.6
6.4.7
Stall angle
167
6.4.6.1
Pressure and velocity contours
167
6.4.6.2
Dropping lifts and stall angle
168
Comparison of the affect of design parameters
169
6.4.7.1
Lift coefficient
169
6.4.7.2
Drag coefficient
170
6.4.7.3
Lift to drag ratio
172
6.4.7.4
Moment coefficient and centre of
pressure
7
165
173
6.5 Fuel consumption and CO2 emission
175
CONCLUSION AND FUTURE WORK
178
7.1 Conclusion
178
7.2 Recommendation for Further Work
181
REFERENCES
182
Appendices A-C
194-213
xiii
LIST OF TABLES
TABLE NO.
TITLE
PAGE
3.1
Mesh elements
61
3.2
Type of meshing scheme.
61
3.3
The load capacities of JR3 sensor
67
3.4
Principle dimension of wings
69
4.1
Principle dimension of wings.
76
4.2
Lift coefficient versus angle of attack for h/c = 0.1 and
AR = 1 based on experimental and numerical result
4.3
Lift coefficient versus ground clearance for angle of attack
2º and AR = 1 based on experimental and numerical result
4.4
85
Drag coefficient versus angle of attack with h/c = 0.1and
AR = 1.25 for rectangular and compound wing
4.11
85
Lift coefficient versus ground clearance with angle of attack
2º and AR = 1.25 for rectangular and compound wing
4.10
83
Lift coefficient versus angle of attack with h/c = 0.1and
AR = 1.25 for rectangular and compound wing
4.9
83
Lift to drag ratio versus ground clearance for angle of attack
2º and AR = 1 based on experimental and numerical result
4.8
81
Lift to drag ratio versus angle of attack for h/c = 0.1and
AR = 1 based on experimental and numerical result
4.7
81
Drag coefficient versus ground clearance for angle of attack
2º and AR = 1 based on experimental and numerical result
4.6
79
Drag coefficient versus angle of attack for h/c = 0.1and
AR = 1 based on experimental and numerical result
4.5
79
87
Drag coefficient versus ground clearance with angle of
attack 2º and AR = 1.25 for rectangular and compound wing
87
xiv
4.12
Lift to drag ratio versus angle of attack with h/c = 0.1 and
AR = 1.25 for rectangular and compound wing
4.13
89
Lift to drag ratio versus ground clearance with angle of
attack 2º and AR = 1.25 for rectangular and compound wing
89
5.1
Reynolds number
96
6.1
Principle dimension of rectangular wing and compound
wings with different middle wing span
6.2
Principle dimension of compound wings with different
anhedral angle
6.3
112
Principle dimension of compound wings with different taper
ratio
6.4
112
113
Lift coefficient versus Angle of attack with ground
clearance (h/c) of 0.15 and AR = 1.25 for experimental and
present numerical result
6.5
115
Drag coefficient versus Angle of attack with ground
clearance (h/c) of 0.15 and AR = 1.25 for experimental and
present numerical result
6.6
116
Lift to drag ratio versus Angle of attack with ground
clearance (h/c) of 0.15 and AR = 1.25 for experimental and
present numerical result
6.7
117
Lift coefficient and increment (In) versus angle of attack
(A) at ground clearance (h/c) of 0.15 for rectangular (R) and
compound wings (C)
6.8
123
Drag coefficient and reduction (Re) versus angle of attack
(A) at ground clearance (h/c) of 0.15 for rectangular (R) and
compound wings
6.9
124
Lift to drag ratio and increment (In) versus angle of attack
(A) at ground clearance (h/c) of 0.15 for rectangular (R) and
compound wings (C)
6.10
126
Moment coefficient and reduction (Re) versus angle of
attack (A) at ground clearance (h/c) of 0.15 for rectangular
(R) and compound wings (C)
127
xv
6.11
Centre of pressure coefficient and reduction (Re) versus
angle of attack (A) at ground clearance (h/c) of 0.15 for
rectangular (R) and compound wings (C)
6.12
Lift coefficient and its increment versus anhedral angle at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.13
147
Centre of pressure and its reduction versus taper ratio at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.22
145
Moment coefficient and its reduction versus taper ratio at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.21
144
Lift to drag ratio and its increment versus taper ratio at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.20
143
Drag coefficient and its reduction versus taper ratio at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.19
139
Lift coefficient and its reduction versus taper ratio (TR) at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.18
138
Centre of pressure and its reduction versus anhedral angle at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.17
136
Moment coefficient and its increment versus anhedral angle
at ground clearance (h/c) of 0.15 and angle of attack of 4°
6.16
135
Lift to drag ratio and its increment versus anhedral angle at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.15
134
Drag coefficient and its reduction versus anhedral angle at
ground clearance (h/c) of 0.15 and angle of attack of 4°
6.14
128
148
Lift coefficient and its increment versus ground clearance at
angle of attack of 4º for rectangular wing and compound
wing-1
6.23
152
Drag coefficient and its reduction versus ground clearance
at angle of attack of 4º for rectangular wing and compound
wing-1
6.24.
153
Lift to drag ratio and its increment versus ground clearance
at angle of attack of 4º for rectangular wing and compound
wing-1
155
xvi
6.25.
Moment coefficient and its reduction versus ground
clearance at angle of attack of 4º for rectangular wing and
compound wing-1
6.26
156
Centre of pressure and its reduction versus ground clearance
at angle of attack of 4º for rectangular wing and compound
wing-1
6.27
157
Lift coefficient and its increment versus Reynolds number
at ground clearance of 0.15 and angle of attack of 4º for
rectangular wing and compound wing-4
6.28
161
Drag coefficient and its reduction versus Reynolds number
at ground clearance of 0.15 and angle of attack of 2º for
rectangular wing and compound wing-4
6.29
163
Lift to drag ratio and its increment versus Reynolds number
at ground clearance of 0.15 and angle of attack of 2º for
rectangular wing and compound wing-4
6.30
164
Moment coefficient and its reduction versus Reynolds
number at ground clearance of 0.15 and angle of attack of 2º
for rectangular wing and compound wing-4
6.31
165
Centre of pressure and its reduction versus Reynolds
number at ground clearance of 0.15 and angle of attack of 2º
for rectangular wing and compound wing-4
6.32
166
Lift coefficient and its increment versus angle of attack at
ground clearance of 0.15 for compound wing-1 and
compound wing-7
6.33
170
Drag coefficient and its increment versus angle of attack at
ground clearance of 0.15 for compound wing-1 and
compound wing-7
6.34
171
Lift to drag ratio and its increment versus angle of attack at
ground clearance of 0.15 for compound wing-1 and
compound wing-7
6.35.
172
Moment coefficient and its reduction versus angle of attack
at ground clearance of 0.15 for compound wing-1 and
compound wing-7
174
xvii
6.36
Centre of pressure and its reduction versus angle of attack at
ground clearance of 0.15 for compound wing-1 and
compound wing-7
6.37
Rate of fuel consumption and CO2 emission of wings versus
angle of attack for h/c = 0.1 and AR = 1.25
6.38
175
176
Rate of fuel consumption and CO2 emission of rectangular
wing and compound wing-1 versus ground clearance for
angle of attack of 4° and AR = 1.25
177
xviii
LIST OF FIGURES
FIGURE NO.
2.1
TITLE
Aerodynamic coefficient of front wing versus angle of
attack (Kieffer et al., 2006)
2.2
PAGE
27
WIG craft on wavy surface with course angle β(Yang et
al., 2010b)
28
2.3
Periodic aerodynamic coefficients (Yang et al., 2010b)
29
2.4
Cyclic roll moment (Yang et al., 2010b)
30
2.5
Multi-element wing (Xuguo et al., 2009)
32
2.6
Aerodynamic coefficients versus ground clearance (Xuguo
et al., 2009)
2.7
33
Aerodynamic forces versus ground clearance (h/c) for
different relative jet velocity (vjet/v∞), and angle of attack
θ° =0 (Yang and Yang, 2010)
2.8
35
Aerodynamic forces versus angle of attack (θ°) for
different relative jet velocity (vjet/v∞), and h/c=0. 3 (Yang
and Yang, 2010)
2.9
35
Aerodynamic forces versus nozzle angle (θ°) for different
ground clearance (h/c) (Yang and Yang, 2011)
36
2.10
Power-augmented ram vehicle (Matveev, 2008)
36
2.11
Amphibious craft (Sitek and Yang, 2011)
37
2.12
The pollutant emissions for several years (Kurniawan and
Khardi, 2011)
41
3.1
Compound wing
42
3.2
Near-wall modelling
53
3.3
Pressure-based solver, (a) segregated algorithm,
(b) coupled algorithm
56
xix
3.4
Mesh element and type of meshing near region from wing
62
3.5
Meshing of whole region around the wing
62
3.6
Universiti Teknologi Malaysia low speed wind tunnel
(Mansor, 2009)
3.7
65
The test section and a 6-components balance/load-cell to
measure aerodynamic forces and moment in 3 dimensional
loads (Mansor, 2009)
3.8
66
Power consumption of motor versus wind speed (Mansor,
2009)
66
3.9
JR3 sensor NO. 50M31A3-125 (JR3, Inc)
67
3.10
Facility of control room (Mansor, 2009)
68
3.11
Types of wing configuration, (a) Rectangular wing, (b)
Compound wing
69
3.12
Sketch of (a) Rectangular wing, (b) Compound wing
69
3.13
Experimental setup in low speed wind tunnel of Universiti
Teknologi Malaysia
70
3.14
Wing mounting by one strut
71
3.15
Supporting system
72
3.16
Monitoring force measurements
72
4.1
Types of wing configuration, (a) Rectangular wing, (b)
Compound wing, (c) Explanation of compound wing
4.2
75
Grid independency of numerical simulation, (a) Lift
coefficient, (b) Drag coefficient
77
4. 3
Meshing of rectangular wing
77
4. 4
Meshing of compound wing
78
4.5
Lift coefficient versus angle of attack for h/c = 0.1 and
AR = 1
4.6
Lift coefficient versus ground clearance for angle of
attack 2º and AR = 1
4.7
80
Drag coefficient versus angle of attack for h/c = 0.1 and
AR = 1
4.8
79
81
Drag coefficient versus ground clearance for angle of
attack 2º and AR= 1
82
xx
4.9
Lift to drag ratio versus angle of attack for h/c = 0.1 and
AR = 1
4.10
Lift to drag ratio versus ground clearance for angle of
attack 2º and AR=1
4.11
88
Lift to drag ratio versus angle of attack for h/c = 0.1 and
AR = 1.25
4.16
88
Drag coefficient versus ground clearance for angle of
attack 2º and AR = 1.25
4.15
86
Drag coefficient versus angle of attack for h/c = 0.1 and
AR = 1.25
4.14
86
Lift coefficient versus ground clearance for angle of attack
2º and AR = 1.25
4.13
84
Lift coefficient versus angle of attack for h/c = 0.1 and
AR = 1.25
4.12
83
90
Lift to drag ratio versus ground clearance for angle of
attack 2º and AR = 1.25
90
5.1
Mounting of compound wing inside UTM-LST
91
5.2
Repeatability of experimental test (a) Lift coefficient and
(b) drag coefficient
5.3
92
Lift coefficient versus ground clearance (h/c) at different
angle of attack (AOA) and air speed for a) rectangular
wing and b) compound wing
5.4
93
Drag coefficient versus ground clearance (h/c) at
different angle (AOA) of attack and air speed for a)
rectangular wing and b) compound wing
5.5
94
Moment coefficient versus ground clearance (h/c) at
different angle of attack (AOA) and air speed for a)
rectangular wing and b) compound wing
5.6
95
Lift coefficient of rectangular and compound wing versus
angle of attack (α°) for different ground clearance (h/c)
and Reynolds number (Re)
98
xxi
5.7
Drag coefficient of rectangular and compound wing versus
angle of attack (α°) for different ground clearance (h/c)
and Reynolds number (Re)
5.8
100
Lift to drag ratio of rectangular and compound wing versus
angle of attack (α°) for different ground clearance (h/c)
and Reynolds number (Re)
5.9
Drag polar of rectangular and compound wing for different
ground clearance (h/c) and Reynolds number (Re)
5.10
102
104
Moment coefficient of rectangular and compound wing
versus angle of attack (α°) for different ground clearance
(h/c) and Reynolds number (Re)
5.11
106
Center of pressure of rectangular and compound wing
versus angle of attack (α°) for different ground clearance
(h/c) and Reynolds number (Re)
5.12
108
Comparison of experimental and numerical simulation
results at ground clearance of 0.15, (a) Lift coefficient,
(b) Drag coefficient, (c) Lift to drag ratio
6.1
Types of wing configuration, (a) Rectangular wing, (b)
Compound wing, (c) Explanation of the compound wing
6.2
109
111
Grid independency of numerical simulation, (a) Lift
coefficient, (b) Drag coefficient
113
6.3
Meshing of rectangular wing
114
6.4
Meshing of compound wing
114
6.5
Lift coefficient (CL) versus angle of attack for ground
clearance (h/c) of 0.15 and AR = 1.25
6.6.
Drag coefficient (CD) versus angle of attack for ground
clearance (h/c) of 0.15 and AR = 1.25
6.7
118
Pressure coefficient contour on upper and lower surface of
wings at ground clearance of 0.15 and angle of attack of 8°
6.9
117
Lift to drag ratio (L/D) versus angle of attack for ground
clearance (h/c) of 0.15 and AR = 1.25
6.8
116
119
Pressure coefficient contour on the middle span of wings
at ground clearance of 0.15 and angle of attack of 8°
120
xxii
6.10
Velocity vector colored by pressure coefficient on the
middle span of wings at ground clearance of 0.15 and
angle of attack of 8°
6.11
Velocity contour (m/s) on middle span of wings at
ground clearance of 0.15 and angle of attack of 8°
6.12
120
121
Velocity vector colored by velocity magnitude (m/s) on
the middle span of wings at ground clearance of 0.15 and
angle of attack of 8°
6.13
Pressure coefficient distribution near wingtip of wings at
ground clearance of 0.15 and angle of attack of 8°
6.14
128
Centre of pressure (XCP/c) versus angle of attack at ground
clearance (h/c) of 0.15
6.19
126
Moment coefficient (CM) versus angle of attack at ground
clearance (h/c) of 0.15
6.18
125
Lift to drag ratio (L/D) versus angle of attack at ground
clearance (h/c) of 0.15
6.17
123
Drag coefficient (CD) versus angle of attack at ground
clearance (h/c) of 0.15
6.16
122
Lift coefficient (CL) versus angle of attack at ground
clearance (h/c) of 0.15
6.15
121
129
Pressure coefficient contour on upper and lower surface of
compound wings at ground clearance of 0.15 and angle of
attack of 4°
6.20
130
Pressure coefficient contour on the middle span of
compound wings at ground clearance of 0.15 and angle
of attack of 4°
6.21
131
Velocity vector colored by pressure coefficient on the
middle span of compound wings at ground clearance of
0.15 and angle of attack of 4°
6.22
131
Velocity contour (m/s) on the middle span of compound
wings at ground clearance of 4.15 and angle of attack of 4°
132
xxiii
6.23
Velocity vector colored by velocity magnitude (m/s) on the
middle span of compound wings at ground clearance of
0.15 and angle of attack of 4°
6.24
Pressure coefficient distribution near wingtip of compound
wings at ground clearance of 0.15 and angle of attack of 4°
6.25
138
Centre of pressure (XCP/c) versus anhedral angle at ground
clearance of 0.15 and angle of attack of 4°
6.30
137
Moment coefficient (CM) versus anhedral angle at
ground clearance of 0.15 and angle of attack of 4°
6.29
135
Lift to drag ratio (L/D) versus anhedral angle at ground
clearance of 0.15 and angle of attack of 4°
6.28
134
Drag coefficient (CD) versus anhedral angle at ground
clearance of 0.15 and angle of attack of 4°
6.27
133
Lift coefficient (CL) versus anhedral angle at ground
clearance of 0.15 and angle of attack of 4°
6.26
132
139
Pressure coefficient contour on upper and lower surface of
compound wings at ground clearance of 0.15 and angle of
attack of 4°
6.31
140
Pressure coefficient contour on the middle span of
compound wings at ground clearance of 0.15 and angle of
attack of 4°
6.32
Velocity contour (m/s) on the middle span of compound
wings at ground clearance of 0.15 and angle of attack of 4°
6.33
144
Lift to drag ratio (L/D) versus taper ratio at ground
clearance of 0.15 and angle of attack of 4°
6.37
143
Drag coefficient (CD) versus taper ratio at ground
clearance of 0.15 and angle of attack of 4°
6.36
142
Lift coefficient (CL) versus taper ratio at ground clearance
of 0.15 and angle of attack of 4°
6.35
141
Pressure coefficient distribution near wingtip of compound
wings at ground clearance of 0.15 and angle of attack of 4°
6.34
141
146
Moment coefficient (CM) versus taper ratio at ground
clearance of 0.15 and angle of attack of 4°
147
xxiv
6.38
Centre of pressure (XCP/c) versus taper ratio at ground
clearance of 0.15 and angle of attack of 4°
6.39
148
Pressure coefficient contour on upper and lower surface
of compound wing-1 at ground clearances of 0.1 and 0.4
with angle of attack of 4°
6.40
149
Pressure coefficient contour on the middle span of
compound wing-1 at ground clearances of 0.1 and 0.4 with
angle of attack of 4°
6.41
150
Velocity vector colored by pressure coefficient on the
middle span of compound wing-1 at ground clearances of
0.1 and 0.4 with angle of attack of 4°
6.42
150
Velocity contour (m/s) on the middle span of compound
wing-1 at ground clearances of 0.1 and 0.4 with angle of
attack of 4°
6.43
150
Velocity vector colored by velocity magnitude (m/s) on
the middle span of compound wing-1 at ground clearances
of 0.1 and 0.4 with angle of attack of 4°
6.44
151
Pressure coefficient distribution near wingtip of compound
wing-1 at ground clearances of 0.1and 0.4 with angle of
attack of 4°
6.45
Lift coefficient (CL) versus ground clearance at angle of
attack of 4°
6.46
155
Moment coefficient (CM) versus ground clearance at
angle of attack of 4°
6.49
154
Lift to drag ratio (L/D) versus ground clearance at angle of
attack of 4°
6.48
152
Drag coefficient (CD) versus ground clearance at angle
of attack of 4°
6.47
151
157
Centre of pressure (XCP/c) versus ground clearance at
angle of attack of 4°
158
xxv
6.50
Pressure coefficient contour on upper and lower surface
of compound wing-4 for different Reynolds number at
ground clearance of 0.15 and angle of attack of 4°
6.51
159
Pressure coefficient contour on the middle span of
compound wing-4 for different Reynolds number at
ground clearance of 0.15 and angle of attack of 4°
6.52
160
Pressure coefficient distribution near wingtip of compound
wing-4 for different Reynolds number at ground
clearances of 0.15 and angle of attack of 4°
6.53
Lift coefficient (CL) versus Reynolds number at ground
clearance of 0.15 and angle of attack of 4°
6.54
166
Centre of pressure (XCP/c) versus Reynolds number at
ground clearance of 0.15 and angle of attack of 4°
6.58
164
Moment coefficient (CM) versus Reynolds number at
ground clearance of 0.15 and angle of attack of 4°
6.57
163
Lift to drag ratio (L/D) versus Reynolds number at
ground clearance of 0.15 and angle of attack of 4°
6.56
162
Drag coefficient (CD) versus Reynolds number at ground
clearance of 0.15 and angle of attack of 4°
6.55
160
167
Pressure coefficient contour on upper and lower surface of
compound wing-7 at stall angle and ground clearance of
0.15
6.59
168
Pressure coefficient and velocity contour (m/s) on the
middle span of compound wing-7 at stall angle and
ground clearance of 0.15
6.60
Stall angle of rectangular wing and compound wing-7 at
ground clearance of 0.15
6.61
170
Drag coefficient (CD) versus angle of attack at ground
clearance of 0.15
6.63
169
Lift coefficient (CL) versus angle of attack at ground
clearance of 0.15
6.62
168
171
Lift to drag ratio (L/D) versus angle of attack at ground
clearance of 0.15
173
xxvi
6.64
Moment coefficient (CM) versus angle of attack at ground
clearance of 0.15
6.65
174
Centre of pressure (XCP/c) versus angle of attack at ground
clearance of 0.15
175
xxvii
LIST OF ABBREVIATIONS
AEV
-
Aero-levitation Electric Vehicle
SL
-
Sliding mesh
AOA
-
Angle of attack
AR
-
Aspect ratio
CFD
-
Computational fluids dynamic
CoVGs
-
Co-rotating vortex generators
CtLVG
-
Counter-rotating large vortex generators
CtSVGs
-
Counter-rotating subboundary layer vortex generators
DARS
Data Acquisition and Reduction System
DM
-
Dynamic mesh
FS
-
Forward swept
FVM
-
Finite volume Method
HAPs
-
Hazardous air pollutants
HS
-
Height stability
LDA
-
Laser Doppler Anemometry
LTO
-
Landing and take off
LVGs
-
Large-scale vortex generators
PAR
-
Power augmented ram
PARV
-
Power-augmented ram vehicle
PDS
-
Propeller-deflected slipstream
PIV
-
Particle image velocimetry
RANS
-
Reynolds averaged Navier-Stokes
RFS
-
Reverse forward swept
SQP
-
Sequential quadratic programming method
SVGs
-
Subboundary layer vortex generators
TAF
-
Tandem-Airfoil-Flairboat
xxviii
UTM-LST
-
Low speed wind tunnel of Universiti Teknologi Malaysia
VGs
-
Vortex generators
VLM
-
Vortex lattice method
WIG
-
Wing-in- ground effect
xxix
LIST OF SYMBOLS
a
Anhedral angle
b
Wing Span
bm
Middle wing span
c
Chord length
ct
Tip chord length
CL
Lift Coefficient
CD
Drag Coefficient
CM
Moment coefficient
CP
Specific fuel combustion
D
Drag Force
d
Diameter of cylinder
Gb
Generation of turbulence kinetic energy due to
buoyancy
Gk
Generation of turbulence kinetic energy due to the mean
velocity gradients
Gω
Production of ω
h
Height of trailing edge of the wing above the ground
h/c
Ground clearance
I
Turbulence Intensity
K
Mean kinetic energy
k
Turbulent kinetic energy
kP
Turbulence kinetic energy k at the near-wall node P
k(t)
Total kinetic energy
L
Lift force
L
Characteristics length
l
Turbulence Length Scale
xxx
L/D
Lift to drag ratio
M
Pitching moment at c/4 from the leading edge
m& CO 2
Rate of CO2 emission
m& f
Rate of fuel consumption
P
Mean normal pressure
p
Normal pressure
S
Wing planform area
SE
Specific energy
SCE
Specific CO2 emission
Sij
Mean rate of deformation tensor
s'ij
Fluctuating rate of deformation tensor
Sk
User-defined source term for k
Sω
User-defined source term for ω
TSFC
Trust specific fuel consumption
U
Free stream mean velocity
U
Mean velocity in x direction
*
U
Mean velocity of flow near-wall region
Umax
Maximum velocity at a distance x downstream of the
source
UP
Mean velocity of flow at the near-wall node P
u
Velocity in x direction
uj
Velocity in jth direction
uτ
Friction velocity
u'
Fluctuating velocity in x direction
u+
Nondimensional velocity of flow
V
Mean velocity in y direction
v
Velocity in y direction
vjet
Jet velocity
v∞
velocity at infinity
v'
Fluctuating velocity in y direction
W
Mean velocity in Z direction
Wi
Initial weight
Wf
Fuel weight
xxxi
w
Velocity in z direction
w'
Fluctuating velocity in z direction
X CP
Centre of pressure from the leading edge
Xh
Height aerodynamic center
Xα
Pitch aerodynamic center
x
Coordinate in ith direction
YM
Effects of compressibility on turbulence
Yk
Dissipation of k due to turbulence
Yω
Dissipation of ω due to turbulence
y
Height of first mesh on wing
y
Coordinate in jth direction
yp
Distance from point P to the wall
y+
Nondimensional wall distance
z
Coordinate in kth direction
α
Angle of attack
α
Under-relaxation factor
β
Course angle
θ
Nozzle angle
λ
Taper ratio (c/ct)
μ
Air viscosity
μt
Turbulent viscosity
ηp
Propeller efficiency
ε
Turbulent energy dissipation rate
ω
Turbulence frequency
ρ
Air density
Γk
Effective diffusivity of k
Γω
Effective diffusivity of ω
τw
Wall shear stress
φ
Quantities value of upstream cell-centre
φcalc
Calculated value of quantity φ face
φf
Quantity value of cell face
φnew
New value of quantity φ
φold
Old value of quantity φ
xxxii
LIST OF APPENDICES
APPENDIX
A
TITLE
Aerodynamic characteristics of wing of wig catamaran
vehicle in ground effect
B
C
PAGE
192
Numerical investigation on fuel consumption of wig
catamaran craft in ground effect
203
Publications
209