This document discusses airfoils and provides calculations related to airfoil design codes and performance corrections. It defines an airfoil as the cross-sectional shape of a wing, blade, or other aerodynamic surface. The document discusses different airfoil types and codes, such as the NACA 4-digit system relating to maximum camber, thickness, and position of maximum thickness. It then shows calculations correcting for these properties, as well as lift and pressure coefficients, for different airfoils. In the end, it provides a sample calculation correcting angular velocity and pressure coefficients for a new airfoil code based on thickness comparisons to an original airfoil.

1. E-mail: Hussein.Mohamed@eng.psu.edu.eg
Mobil: +2 01555 96 888 1
Ph.D. and M.Sc. In Ship Hydrodynamics

2. What is Aero foil??
 An airfoil or aerofoil is the cross-sectional shape of a wing
blade of a propeller rotor or turbine; or sail as seen in cross-
section

3. Applications
Aero plan Wing Marine Propeller Rudder

4. Aero foil Types

5. Aims of Aero foil

6. General Definitions

7. General Definitions

8. Aero foil Code
 National Advisory Committee for Aeronautics (NACA).
 It is defined by series with four digit xxxx or five digit xxxxx
Max. camber percentage of chord
Max. Thickness of chord %
Position of Maximum Thickness of chord%

9. Problem

11. • Correction due to thickness
• Correction due to angle of attack
• Correction due to Camber
S=(Max. of camber thickness NACA-new/ Max. of camber thickness NACA-new)* CL,OLD -
Correction=(S)- CL,New
(𝐯/𝐕)𝑵𝒆𝒘 = ((𝐯/𝐕)𝒐𝒍𝒅
-1)*(𝐭)𝐧𝐞𝐰/(𝐭)𝐨𝐥𝐝 ]+1
Correction=(Max. of camber thickness NACA-new/ Max. of camber thickness NACA-old)
(∆𝐯/𝐕)𝑵𝒆𝒘 = (∆𝐯/𝐕)𝒐𝒍𝒅∗ 𝑪𝒐𝒓𝒓𝒆𝒄𝒕𝒊𝒐𝒏
(∆va/V)𝑁𝑒𝑤 = (∆v/V)𝑜𝑙𝑑∗ 𝐶𝑜𝑟𝑟𝑒𝑐𝑡𝑖𝑜𝑛
Corrections and Formula Represent the angle of attack, lift coefficient CL
Represent the thickness
Represent the thickness of camber

12. Back (B)
Face (F)
• ∆ v V 𝐵𝑎𝑐𝑘 =
𝑣
𝑉
+
∆va
V
+ ∆ v V
• ∆ v V 𝐹𝑎𝑐𝑒 =
𝑣
𝑉
−
∆va
V
− ∆ v V
• ∆ p q 𝐵𝑎𝑐𝑘 = 1 − ∆ ve V 𝐵𝑎𝑐𝑘^2
• ∆ p q 𝐹𝑎𝑐𝑒 = 1 − ∆ v𝑒 V 𝐹𝑎𝑐𝑒^2
Corrections and Formula

13. Problem

14. Solution
80
50
30
10
5
C%
1.022
1.108
1.162
1.188
1.174
v/V
=-0.153*0.068
=-0.153*0.149
=-0.153*0.239
=-0.153*0.479
=-0.153*0.685
=4/6*0.159
=4/6*0.228
=4/6*0.260
=4/6*0.187
=4/6*0.137
1.118
1.238
1.299
1.239
1.174
-0.153*0.685+
4/6*0.137
∆ v𝑒 V 𝐵𝑎𝑐𝑘
0.926
0.978
1.025
1.137
1.174
+0.153*0.685-
4/6*0.137
∆ ve V 𝐹𝑎𝑐𝑒
-0.249
-0.532
-0.687
-0.535
-0.349
∆ p q 𝐵𝑎𝑐𝑘
0.142
0.043
-0.05
-0.292
-0.408
∆ p q 𝐹𝑎𝑐𝑒

15. Solution
S=(Max. of camber thickness NACA-new/ Max. of camber thickness NACA-new)* CL,OLD - 4/6*0.76
Correction=(S)- CL,New
=(4/6*0.76)-0.66=-0.1053
(∆va/V)𝑁𝑒𝑤 = (∆va/V)𝑜𝑙𝑑∗ 𝐶𝑜𝑟𝑟𝑒𝑐𝑡𝑖𝑜𝑛
Correction=(Max. of camber thickness NACA-new/ Max. of camber thickness NACA-old) =4/6

16. ∆ p q
𝑐%
5 10
20 30 50 70 80
-0.1
0.0
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
1
0.1
0.2
0.3
0.4
0.5
0.6
0.7
1.0
Back
Face

17. E-mail: Hussein.Mohamed@eng.psu.edu.eg
Mobil: +2 01555 96 888 1
Ph.D. and M.Sc. In Ship Hydrodynamics