AERO40001 Aerodynamics I Section 1-4
__________________________________________________________________________
Outline
• Define the geometric parameters of an aerofoil.
• Describe the relationship between lift and how it is affected by aerofoil geometry
and angle of attack.
• Introduce basic flow over an aerofoil and the boundary layer.
• Consider different types of separation form an aerofoil.
With the advent of successful powered flight there was a great interest in understanding of the
aerodynamic action of lifting surfaces. From 1912-1918 the analysis of an airplane wing
took a giant step forward when Ludwig Prandtl and his colleagues at Gottingen, Germany,
showed that the aerodynamic consideration of wings could be split into two parts
(1) the study of the section of a wing or
(2) the modification of such aerofoil properties to account for the complete wing.
This approach is still used today.
AE2-201 Aerodynamics Part II
Thickness distribution
;]
Anatomy of an aerofoil
Anatomy of an aerofoil f-
n
mtdna awdwicanso
image !
÷foihg
Leading edge: most forward point*
Trailing edge: most rearward point -
chord
Upper surface = suction side
Lower surface = pressure side -
The chord line
4
Image: Olivier Cleynen, Creative Commons
• Connects L.E and T.E.
• Flow incidence is defined relative to the chord
line
t.TT
1
, AE2-201 Aerodynamics Part II
AERO40001 Aerodynamics I Section 1-4
Will
define Coffin
.tt?wheowoi
__________________________________________________________________________
AoA and pressureimplies
distribution
Angle of Attack and pressure distribution
suction
-
6
negative Cp
(
Cp Pressure
¥rEsrhm
-
-
coefficient
✓
Pressure distribution
(
surface ←
on
upper O
<
Djgrence between thickness
two lines summed
denotes the
Cgt
-
up
- Area between
the curves
www. distribution
surface pressure
→
stagnation
AE2-201 Aerodynamics Part point
II
it hasto
Afterglow goes past
suction
peak conditions and this
adverse
recover
through
and
go
Lift vs angle of attack:
can lead to separation
from
E top of -
-
qgu-zah.gl
coefficient µ
g sudden drop
of stall
for small afraid) lift with alinearly
varies
oil stall
dge stall attack
dge stall angle of
2
27
__________________________________________________________________________
Outline
• Define the geometric parameters of an aerofoil.
• Describe the relationship between lift and how it is affected by aerofoil geometry
and angle of attack.
• Introduce basic flow over an aerofoil and the boundary layer.
• Consider different types of separation form an aerofoil.
With the advent of successful powered flight there was a great interest in understanding of the
aerodynamic action of lifting surfaces. From 1912-1918 the analysis of an airplane wing
took a giant step forward when Ludwig Prandtl and his colleagues at Gottingen, Germany,
showed that the aerodynamic consideration of wings could be split into two parts
(1) the study of the section of a wing or
(2) the modification of such aerofoil properties to account for the complete wing.
This approach is still used today.
AE2-201 Aerodynamics Part II
Thickness distribution
;]
Anatomy of an aerofoil
Anatomy of an aerofoil f-
n
mtdna awdwicanso
image !
÷foihg
Leading edge: most forward point*
Trailing edge: most rearward point -
chord
Upper surface = suction side
Lower surface = pressure side -
The chord line
4
Image: Olivier Cleynen, Creative Commons
• Connects L.E and T.E.
• Flow incidence is defined relative to the chord
line
t.TT
1
, AE2-201 Aerodynamics Part II
AERO40001 Aerodynamics I Section 1-4
Will
define Coffin
.tt?wheowoi
__________________________________________________________________________
AoA and pressureimplies
distribution
Angle of Attack and pressure distribution
suction
-
6
negative Cp
(
Cp Pressure
¥rEsrhm
-
-
coefficient
✓
Pressure distribution
(
surface ←
on
upper O
<
Djgrence between thickness
two lines summed
denotes the
Cgt
-
up
- Area between
the curves
www. distribution
surface pressure
→
stagnation
AE2-201 Aerodynamics Part point
II
it hasto
Afterglow goes past
suction
peak conditions and this
adverse
recover
through
and
go
Lift vs angle of attack:
can lead to separation
from
E top of -
-
qgu-zah.gl
coefficient µ
g sudden drop
of stall
for small afraid) lift with alinearly
varies
oil stall
dge stall attack
dge stall angle of
2
27
