my beloved family and fabricating subsonic wing.pdfapproval sheet the project report attached here...
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Approval Sheet
The project report attached here to, entitle "Modelling and Fabricating Subsonic
Wing" prepared and submitted by Khairul Amin bin Othman in partial fulfillment of
the requirement for Bachelor of Engineering with Honours in Mechanical Engineering
and Manufacturing System in hereby read and approved by:
ý ýýýý -, -2- S 20 0 s-
Dr. Mohhril bin Osman Date Supervisor MEl 2005
MODELLING AND FABRICATING SUBSONIC WING
KHAIRUL AMIN BIN OTHMAN
This project is submitted in partial fulfillment of the requirements for the degree of Bachelor of Engineering with Honours
(Mechanical Engineering and Manufacturing Systems)
Faculty of Engineering UNIVERSITI MALAYSIA SARAWAK
2004
For my Father and Mother And
My beloved family
ACKNOWLEDGEMENTS
Alhamdulillah, Thank God for all His blessing and permission I was able to
complete this Final Year Project. First and foremost I would like to take this
opportunity to thank my supervisor, Dr. Mohd. Shahril Osman for his valuable
advices, his patience and willingness to assist me completes this report. Without his
support, the work is never have been finished. I would like to mention my special
thanks to my mother and my father, my parents for their continuous encouragement
and support in my life. I am forever grateful to them for that.
I would like to thank Mr Masri and Mr Rhyier and other lab technicians for
their willing to work overtime n enabling me to collect necessary data and prepare
the tools and machines that needed in this project. They have always been
exceptionally helpful whenever I faced any problem in developing the experimental
set up.
I am grateful to all my supportive friends and mechanical lecturers, without their
help I would be still taking data. Last but no the least, I want to expressed my thank to
my roommate. Nizam and my friends, Zulkurnain, Dahri especially Elizah for just being
there in my difficult times.
i
ABSTRACT
Aerodynamics is the study of forces and the resulting motion of objects
through the fluid. Aerodynamics affects the motion of a large airliner, a model
rocket, or a kite flying high overhead. The purpose of this study is to determine the
best subsonic wing profile. The airfoil of the wing is developed and fabricated for
test. The aerodynamics characteristics such as lift force and drag force, lift and drag
coefficient, lift drag ratio and other properties is measured and analysed. Several
experiments have been carried out in open subsonic wind tunnel using the four
models of NACA 4- digit airfoil. According to experiment, the maximum model
NACA 1221 has a high lift coefficient which is 1.86882 and NACA 2317 airfoil has
the lowest drag coefficient of 0.01127. In addition, the result is compared with other
experimental past data. From the lift over drag ratio results, we can conclude that
NACA 2317 airfoil model is the effective airfoil compare to the other three tested
airfoil.
11
ABSTRAK
Aerodinamik merupakan kajian tentang daya dan akibat dari pergerakan
objek melalui cecair dan gas. Aerodinamik memberi amat penting kepada kapal
terbang, model roket mahupun pergerakan layang-layang diudara. Kajian ini
bertujuan untuk menentukan dan mencari sayap terbang 'subsonic' yang terbaik.
Dengan itu, 'airfoil' telah direka dan dibentuk untuk digunakan dalam pengkajian ini.
Sifat aerodinamik seperti daya terbang dan daya seretan, koefisien terbang dan
seretan dan juga lain- lain ciri aerodinamik telah diukur dan dianalisis. Beberapa siri
eksperimen telah dibuat dalam terowong udara 'subsonic' terbuka menggunakan
'airfoil' 4- digit NACA yang telah dibuat pada awalnya. Daripada eksperimen itu,
`airfoil' NACA 1221 mempunyai koefisien terbang paling tinggi iaitu 1.86882 dan
'airfoil' NACA 2317 mempunyai koefisien seretan paling rendah 0.01127. Sebagai
tambahan, keputusan eksperimen dibandingkan dengan data dari eksperimen lain.
Dari keputusan bandingan terbang terhadap seretan, dapat disimpulkan bahawa
'airfoil' NACA 2317 merupakan model yang paling effektif dibandingkan dengan
tiga 'airfoil' yang lainnya.
III
CONTENTS
Contents Page Number
ACKNOWLEDGEMENTS
ABSTRACT
ABSTRAK
CONTENTS
LIST OF FIGURE
LIST OF TABLE
NOMENCLATURE
CHAPTER 1: INTRODUCTION
1.0 General Overview of Aerodynamic
1.1 Overview of airplane
1.1.1 Wing Geometry
1.2 Overview of the Project
1.3 Objectives of Project
CHAPTER 2: LITERATURE REVIEW
2.1 Introduction
2.2 NACA Airfoil
2.2.1 NACA 4-Digit Airfoil
2.3 Airfoil Selection
2.4 Airfoil Characteristics
2.4.1 Lift Coefficient
2.4.2 Drag Coefficient
2.4.3 Lift / Drag Ratio
I
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vii
X
Xlll
I
2 3
6
7
9
10
11
11
12
12
13
13
iv
2.5 Angle of Attack
2.6 Factor That Effect the Lift
2.7 Drag
2.7.1 Parasite Drag
2.7.2 Induced Drag
2.7.3 Total Drag
2.8 Speed of Sound
2.9 Mach Number
2.10 Boundary Layer
CHAPTER 3: METHODOLOGY
3.1 Introduction
3.2 Material Selection
3.3 Model and Fabricate Airfoil Model
3.4 Subsonic Wind Tunnel
3.5 Smoke Generator System
3.6 Hanley Innovation VisualFoil
3.7 Experimental Setup
14
15
15
15
16
16
17
18
19
21
21
22
26
27
28
28
CHAPTER 4: EXPERIMENTAL RESULTS AND DISCUSSION
4.1
4.2
Introduction
Result and Discussion
4.2.1 Result of surface roughness of an
airfoil model
4.2.2 Result of subsonic wind tunnel
boundary condition
4.2.3 Results of upstream pressure
4.2.4 Discussion of upstream pressure
4.2.5 Results of downstream pressure
4.2.6 Discussion of downstream pressure
31
31
31
32
33
45
46
60
V
4.2.7 Results of Reynold Number, speed of sound
and Mach number
4.2.8 Discussion of Results of Reynold Number,
speed of sound and Mach number
4.2.9 Results of Lift force, Drag force,
Drag Coefficient and Lift Coefficient
4.2.10 Discussion Results of Lift force, Drag force,
Drag Coefficient and Lift Coefficient
4.3 Limitation of the study
CHAPTER 5: CONCLUSION
61
63
64
80
84
5.1 Conclusion 86
5.2 Recommendation 88
REFERENCES 90
APPENDICES
Appendix A 93
Appendix B 101
Appendix C 102
vi
LIST OF FIGURE
FIGURE
Figure 1.1:
Figure 1.2:
Figure 1.3:
Figure 1.4:
Figure 2.1:
Figure 2.2:
Figure 2.3:
Figure 3.1:
Figure 3.2:
Figure 3.3:
Figure 3.4:
Figure 3.5:
Figure 3.6:
Figure 3.7
Figure 3.8:
PAGE NUMBER
Airplane configuration
Airplane geometry top view
Airplane geometry front view
Airplane geometry side view
Angle of attack
Boundary layer
Laminar and turbulent flow
Top view of airfoil model 2 or airfoil 2617
Side view of airfoil model 1 or airfoil 2413
Top view of airfoil model 2 or airfoil 2617
Side view of airfoil model 2 or airfoil 2617
Top view of airfoil model 3 or airfoil 2417
Side view of airfoil model 3 or airfoil 2417
Top view of airfoil model 4 or airfoil 1221
Side view of airfoil model 4 or airfoil 1221
Figure 3.9: TE54 subsonic wind tunnel
Figure 3.10: Smoke generator system
Figure 3.11: Airfoil is located in working section
of wind tunnel during testing
Figure 4.1: Graph of upstream pressure versus height of working
section of wind tunnel for NACA 2413 airfoil model.
2
3
4
5
14
19
19
23
23
23
24
24
25
25
25
26
27
30
43
vii
Figure 4.2: Graph of upstream pressure versus height of working
section of wind tunnel for NACA 2417 airfoil model. 43
Figure 4.3: Graph of upstream pressure versus height of working
section of wind tunnel for NACA 2317 airfoil model. 44
Figure 4.4: Graph of upstream pressure versus height of working
section of wind tunnel for NACA 1221 airfoil model. 44
Figure 4.5: Graph of downstream pressure versus height of working
section of wind tunnel for NACA 2417 airfoil model. 55
Figure 4.6: Graph of downstream pressure versus height of working
section of wind tunnel for NACA 2413 airfoil model. 55
Figure 4.7: Graph of downstream pressure versus height of working
section of wind tunnel for NACA 2317 airfoil model. 56
Figure 4.8: Graph of downstream pressure versus height of working
section of wind tunnel for NACA 1221 airfoil model. 56
Figure 4.9: Downstream pressure versus height of working
section of wind tunnel for four tested airfoil models
with angle of attack is 5 degrees at different speed 57
Figure 4.10: Downstream pressure versus height of working
section of wind tunnel for four tested airfoil models
with angle of attack is 15 degrees at different speed 58
Figure 4.11: Downstream pressure versus height of working section
of wind tunnel for four tested airfoil models
with angle of attack is 20 degrees at different speed 59
Figure 4.12: Lift coefficient, CL versus angle of attack, a
for NACA 2413 airfoil model 71
viii
Figure 4.13: Lift coefficient, CL versus angle of attack, a
for NACA 2417 airfoil model 71
Figure 4.14: Lift coefficient, CL versus angle of attack, a
for NACA 2317 airfoil model 72
Figure 4.15: Lift coefficient, CL versus angle of attack, a
for NACA 1221 airfoil model 72
Figure 4.16: Comparison of lift coefficient, CL versus
angle of attack, a for airfoil models 73
Figure 4.17: Comparison of drag coefficient, CD versus
angle of attack, a for NACA 2417 airfoil model. 74
Figure 4.18: Comparison of drag coefficient, CD versus
angle of attack, a for NACA 2413 airfoil model. 74
Figure 4.19: Comparison of drag coefficient, CD versus
angle of attack, a for NACA 2317 airfoil model. 75
Figure 4.20: Comparison of drag coefficient, CD versus
angle of attack, a for NACA 1221 airfoil model. 75
Figure 4.21: Comparison of drag coefficient, CD versus
angle of attack, a for airfoil models 76
Figure 4.22: Comparison of lift over drag polar for experiment
airfoil models 77
Figure 4.23: Graph of comparison lift over drag polar for
airfoil models using VisualFoil program. 78
Figure 4.24: Comparison of lift coefficient versus angle of attack
for (a) NACA 2412; (b) NACA 2418.81
Figure 4.25: Drag coefficient versus angle of attack for NACA 2412 airfoil 83
ix
LIST OF TABLE
TABLE PAGE NUMBER
Table 4.1: Surface roughness of airfoil models
Table 4.2: Results of upstream pressure of the airfoil models
with velocity of 35 m/s and a of 5 degree.
Table 4.3: Results of upstream pressure of the airfoil models
with velocity of 35 m/s and a of 15 degree.
Table 4.4: Results of upstream pressure of the airfoil models
with velocity of 35 m/s and a of 20 degree.
Table 4.5: Results of upstream pressure of the airfoil models
with velocity of 25 m/s and a of 5 degree.
Table 4.6: Results of upstream pressure of the airfoil models
with velocity of 25 m/s and a of 15 degree.
Table 4.7: Results of upstream pressure of the airfoil models
with velocity of 25 m/s and a of 20 degree.
Table 4.8: Results of upstream pressure of the airfoil models
with velocity of 15 m/s and a of 5 degree.
Table 4.9: Results of upstream pressure of the airfoil models
with velocity of 15 m/s and a of 15 degree.
Table 4.10: Results of upstream pressure of the airfoil models
with velocity of 15 m/s and a of 20 degree.
Table 4.11: Results of downstream pressure of the airfoil models
32
34
35
36
37
38
39
40
41
42
X
with velocity of 35 m/s and a of 5 degree. 46
Table 4.12: Results of downstream pressure of the airfoil models
with velocity of 35 m/s and a of 15 degree. 47
Table 4.13: Results of downstream pressure of the airfoil models
with velocity of 35 m/s and a of 20 degree. 48
Table 4.14: Results of downstream pressure of the airfoil models
with velocity of 25 m/s and a of 5 degree. 49
Table 4.15: Results of downstream pressure of the airfoil models
with velocity of 25 m/s and a of 15 degree. 50
Table 4.16: Results of downstream pressure of the airfoil models
with velocity of 25 m/s and a of 20 degree. 51
Table 4.17: Results of downstream pressure of the airfoil models
with velocity of 15 m/s and a of 5 degree. 52
Table 4.18: Results of downstream pressure of the airfoil models
with velocity of 15 m/s and a of 15 degree. 53
Table 4.19: Results of downstream pressure of the airfoil models
with velocity of 15 m/s and a of 20 degree. 54
Table 4.20: Result of the Reynold number, speed of sound and
Mach number of the airfoil models 63
Table 4.21: Result of maximum chamber and aspect ratio of the airfoil 65
Table 4.22: Result of the Lift Coefficient, Drag Coefficient the
lift force and the drag force of airfoil model NACA 2413.67
Table 4.23: Result of the Lift Coefficient, Drag Coefficient the
lift force and the drag force of airfoil model NACA 2617.68
Table 4.24: Result of the Lift Coefficient, Drag Coefficient the
lift force and the drag force of airfoil model NACA 2417.69
Table 4.25: Result of the Lift Coefficient, Drag Coefficient the
X1
lift force and the drag force of airfoil model NACA 1221 70
Table 4.26: Result of the Lift / Drag ratio 79
xii
NOMENCLATURES
a: Angle of attack
p Mass density
pa : Local air density
y Ratio of specific heat
v: Kinematics viscosity
AP1 : Dynamic pressure
a: Speed of sound
A: Airfoil area
Ap : Planform area
AR : Aspect ratio
c: Chord
CD : Total drag coefficient
CD; : Induced drag coefficient
CD- Drag of infinite span airfoil
CL Lift coefficient
D Drag force
h /c maximum chamber
L Lift force
L: Length of the airfoil
L/D: Lift drag ratio
Ma : Mach number
Pa : Ambient atmospheric pressure
X111
R: Gas constant
Ra Average roughness
Re : Reynolds number
s: Span
T: Temperature
Ta : Ambient temperature
U External velocity
V: Velocity of wind relative to the body
xiv
Chanter I Iulroduction
Chapter 1
INTRODUCTION
1.0 General Overview of Aerodynamic
Aerodynamics is the study of fluids in motion. Anderson (2001), states that
aerodynamics is an applied science with many practical applications in engineering.
No matter how sophisticated an aerodynamic experiment, may be, the efforts are
usually at one or more of the following practical objectives:
a. The prediction of forces and moments on, and the heat transfer to,
bodies moving through the fluid (usually air).
b. Determination of flows moving internally through the duct.
The application in first item come heading of external aerodynamic since they
deal with external flows over the body. In contrast, the application in second item is
involve internal aerodynamics because they deal with flow internally within ducts.
This project consider to the external aerodynamics of the airplane wing and much
more focusing on the airfoil shape design that will best suit for the subsonic airplane.
1 Modelling trnct f'uhricuting subsonic wing,
Chapter I
1.1 Overview of airplane
JJriruducliun
Airplanes come in many different shapes and sizes. The wings generate most
of the lift to hold the plane in the air. To generate lift, the airplane must be pushed
through the air by the jet engines to provide the thrust to push airplane forward. This
moving will cause the oppose force due to air resistant called drag.
Vertical Stabilizer Control Yaw
Horizontal Stabilizer Control Pitch
Flaps Change Lift and Drag
Aileron Change Rail (Rotate Body)
Spoiler Cockpit
Command and Control Fuselage (Body) Hold Things Together (Carry Payload - Fuel)
Change Lift and Drag (Rotate Body)
Slats Change Lift
Figure 1.1: Airplane configuration (Courtesy from Bensen, 2004)
Figure 1.1 shows the generally airplane parts. wing is located at the centre of
the fuselage. Vertical stabilizer and horizontal stabilizer located at the airplane tail to
provide stability for the airplane, to keep it fly straight. the function of the vertical
stabilizer is to avoid airplane nose from swinging side to side, while horizontal
stabilizer prevent up and down nose motion. Rudder is the hinged part of the vertical
stabilizer, used to deflect the tail to the left and right. The hinged part at the
horizontal called elevator; to deflect the tail up and down as shown in the Figure 1.0.
2 Aladeilittg ancifaGricating subsonic wing
C'htzptar I lniroductron
Aileron and spoiler at the wing used to rotate the body of the airplane; aileron
change the roll and spoiler decrease the lift force when it is deployed.
The wings have additional hinged, rear sections near the body that are called
flaps. Flaps are deployed downward on takeoff and landing to increase the amount of
force produced by the wing. Slat, the front part of the wing will also deflect at
takeoff and landing to produce additional force. The spoilers are also used during
landing to slow the plane down and to counteract the flaps when the airplane is on
the ground.
1.1.1 Wing Geometry
Top View
Top View Trailing Edge
Chord c .
Span ýCeyttezline
,ga
Wing Area A
Leading Edge
Figure 1.2: Airplane geometry top view (Courtesy from Bensen, 2004)
The Figure 1.2 shows a simple wing geometry in the top view. The front of
the wing is called the leading edge; the back of the wing is called the trailing edge.
The distance from the leading edge to the trailing edge is called the chord, denoted
by the symbol, c. The ends of the wing are called the wing tips, and the distance from
one wing tip to the other is called the span, given the symbol, s. The shape of the
3 Modelling and fabricating subsonic wing
Chapter 1 Iniroduetion
wing, when viewed from above looking down onto the wing, is called a planform.
The wing area, A, is the projected area of the planform and is bounded by the leading
and trailing edges and the wing tips.
Front View
Tip Tip
" m" 0 FAWN"" f" or-arY-"r r omr Nrr mi w am
Dihedral Angle
Figure 1.3: Airplane geometry front view (Courtesy from Bensen, 2004)
According to Bensen (2004), the front view of this wing shows that the left
and right wing do not lie in the same plane but meet at an angle. The angle that the
wing makes with the local horizontal is called the dihedral angle. Dihedral is added
to the wings for roll stability; a wing with some dihedral will naturally return to its
original position if it encounters a slight roll displacement. The wing tips are farther
off the ground than the wing root. A negative dihedral angle is called anhedral.
4 Modelling and fahricaling subsonic wing
Chapter I Introduction
Side View
Thickness Mean Camber .. ý Line
Chord Line Camber
Figure 1.4: Airplane geometry side view (Courtesy from Bensen, 2004)
A cut through the wing perpendicular to the leading and trailing edges will
show the cross-section of the wing called an airfoil. The straight line drawn from the
leading to trailing edges of the airfoil is called the chord line. The chord line cuts the
airfoil into an upper surface and a lower surface. Plotting the points that lie halfway
between the upper and lower surfaces, will obtain a curve called the mean camber
line. For a symmetric airfoil (upper surface the same shape as the lower surface) the
mean camber line will fall on top of the chord line. But in most cases, these are two
separate lines. The maximum distance between the two lines is called the camber.
The maximum distance between the upper and lower surfaces is called the thickness.
(Bensen, 2001).
5 iiOft8ll111}; C111dftlj)Ylt'"aling, subs(N1lC wing
Chapter I Irrirurlurtiu»
1.2 Overview of the Project
The project is to fabricate and airplane model and to design the airfoil shape.
So, the part that will consider in this project is the airfoil of the wing. This project
starts with the designing of the airfoil. The reference model to be compared is NACA
four digit series which is model 2412. There are four airfoil model used in this
project which is
" Model 1- The span length is 0.255 m with the chord length is 0.098
m. Maximum chamber thickness is 0.002 m located 0.004 m from the
leading edge. The maximum thickness is 0.0126 m. By using the
NACA four digit systems, the airfoil can be name as 2413 airfoil.
" Model 2- The span length is 0.292 m with the chord length is 0.100
m. Maximum chamber thickness is 0.002 m located 0.006 m from the
leading edge. The maximum thickness is 0.0170 m. By using the
NACA four digit systems, the airfoil can be name as 2617airfoil.
" Model 3- The span length is 0.285 m with the chord length is 0.098
m. Maximum chamber thickness is 0.00275 r located 0.0046 m from
the leading edge. The maximum thickness is 0.0170 m. the airfoil can
be name as 2417 airfoil using the NACA four digit systems.
" Model 4- The span length is 0.290 m with the chord length is 0.099
m. Maximum chamber thickness is 0.0015 m located 0.0017 m from
the leading edge. The maximum thickness is 0.021 m. Using the
NACA four digit systems, the airfoil can be name as 1221 airfoil.
( Modelling rrrrd fuhricating subsonic wing