Flow over an airfoil
Aim: 1.To study flow over an NACA0017 Airfoil at a different angle of attack.
2.To obtain the drag and lift forces at different angle of attack.
Introduction: The NACA airfoils are airfoil shapes for aircraft wings developed by the National Advisory committee for Aeronautics (NACA). The shape of the NACA airfoils is described using a series of digits following the word "NACA". The parameters in the numerical code can be entered into equations to precisely generate the cross-section of the airfoil and calculate its properties.
The NACA four-digit wing sections define the profile by:
- First digit describing maximum camber as percentage of the chord
- Second digit describing the distance of maximum camber from the airfoil leading edge in tenths of the chord.
- Last two digits describing maximum thickness of the airfoil as percent of the chord.
For example, the NACA 2412 airfoil has a maximum camber of 2% located 40% (0.4 chords) from the leading edge with a maximum thickness of 12% of the chord.
The NACA 0015 airfoil is symmetrical, the 00 indicating that it has no camber. The 15 indicates that the airfoil has a 15% thickness to chord length ratio: it is 15% as thick as it is long.
Procedure: First step is to create an airfoil which is created by the use of coordinates curve option and then extrude it. The unit system used is 'MKS' unit system in SOLIDWORKS2018. Then after this the flow simulation setup.
1.The analysis will be external and SI system is choosen.
2.Next this is time dependent analysis so total set up time is 5sec at an interval of 1second.
3.Next the fluid choosen is Air with flow type both Laminar and turbulent.
4.Next the velocity is 600m/s in the x-direction.
Result: The meshed airfoil view:
At 0 degree angle of attack:
Pressure Profile
Velocity Profile
Tabulated Data of forces
Here SG Force (X) 1 denotes the surface goal force at x axis that is Drag Force.
SG Force (Y) 1 denotes the surface goal force at y axis that is Lift Force.
DRAG FORCE=302.132N
LIFT FORCE=0.201N
At 2 degree angle of attack:
Pressure Profile
Velocity Profile
Tabulated Data of Forces
Here SG Force (X) 1 denotes the surface goal force at x axis that is Drag Force.
SG Force (Y) 1 denotes the surface goal force at y axis that is Lift Force.
DRAG FORCE=332.685N
LIFT FORCE=834.378N
At 4 degree angle of attack:
Pressure Profile
Velocity Profile
Tabulated Data of Forces
Here SG Force (X) 1 denotes the surface goal force at x axis that is Drag Force.
SG Force (Y) 1 denotes the surface goal force at y axis that is Lift Force.
DRAG FORCE=413.462N
LIFT FORCE=1646.268N
At 6 degree angle of attack:
Pressure Profile
Velocity Profile
Tabulated Data of Forces
Here SG Force (X) 1 denotes the surface goal force at x axis that is Drag Force.
SG Force (Y) 1 denotes the surface goal force at y axis that is Lift Force.
DRAG FORCE=548.111N
LIFT FORCE=2460.983N
At 8 degree angle of attack:
Pressure Profile
Velocity Profile
Tabulated Data of Forces
Here SG Force (X) 1 denotes the surface goal force at x axis that is Drag Force.
SG Force (Y) 1 denotes the surface goal force at y axis that is Lift Force.
DRAG FORCE=754.404N
LIFT FORCE=3244.059N
At 10 Degree angle of Attack:
Pressure Profile
Velocity Profile
Tabulated Data of Forces
Here SG Force (X) 1 denotes the surface goal force at x axis that is Drag Force.
SG Force (Y) 1 denotes the surface goal force at y axis that is Lift Force.
DRAG FORCE=996.389N
LIFT FORCE=4032.270N
Conclusion: At different angle of attack the drag and lift forces obtained are:
| Angle of Attack | Drag Force (in N) | Lift Force (in N) |
| 0 degree | 302.132 | .201 |
| 2 degree | 332.685 | 834.378 |
| 4 degree | 413.462 | 1646.268 |
| 6 degree | 548.111 | 2460.983 |
| 8 degree | 754.404 | 3244.059 |
| 10 degree | 996.389 | 4032.270 |
The following graph shows the comparison bw the forces at different angle of attack:
With this we can conclude that lift force is almost have linear relationship with the angle of attack and the drag force does follow the linear relation but is still increase with the increase in angle of attack.