Flow over an airfoil
PROJECT REPORT
FLOW OVER AN AIRFOIL
INTRODUCTION :
Laminar Flow is the smooth, uninterrupted flow of air over the contour of the wings, fuselage, or other parts of an aircraft in flight. Laminar flow is most often found at the front of a streamlined body and is an important factor in flight. If the smooth flow of air is interrupted over a wing section, turbulence is created which results in a loss of lift and a high degree of drag. An airfoil designed for minimum drag and uninterrupted flow of the boundary layer is called a laminar airfoil.
Angle of Attack (AOA) : In fluid dynamics, The Angle of Attack is the angle at which relative wind meets an Aerofoil. It is the angle formed by the Chord of the aerofoil and the direction of the relative wind or the vector representing the relative motion between the aircraft and the atmosphere. An increase in angle of attack results in an increase in both lift and induced drag, up to a point. Too high an angle of attack (usually around 17 degrees) and the airflow across the upper surface of the aerofoil becomes detached, resulting in a loss of lift, otherwise known as a Stall.
OBJECTIVE :
To model the flow over a NACA0017 Airfoil for the respective angle of attacks 0,2,4,6,8,10 degrees and plot the lift and drag forces for each case. Also, plot the velocity and Pressure Contours.
PROCEDURE :
FIRST, Download the required airfoil from the database and import its coordinates in the solidworks flow simulations.
SECOND, Open sketch, close the airfoil at the end and set the angle of attacks of air.
THIRD, Use extrude option to make the sketch solid, provide some length to it and save it.
FOURTH, open the wizard and set required conditions like external flow, time dependent, air medium, and velocity value for the simulation.
FIFTH, Open the computational domain and increase the domain size. Fix the size in such a way so that we get convincing results.
SIXTH, Surface Goals and Gobal Goals are inserted, and cut plots are also inserted to view the lift and drag.
SEVENTH, Now run the flow simulations, we get the drag force plot and contour plots in the solver tab.
EIGTH, Mesh refinment is incressed and the simulation is get started and results are recorded for post-processing.
RESULTS :
CASE 1 : Angle of Attack = 0 degree
1. CAD Model
2. Velocity Cut Plot
3. Pressure Cut Plot
4. Global Goal Force : x-Direction
5. Global Goal Force : y-Direction
6. Global Goal Friction Force : x-Direction
7. Global Goal Friction Force : y-Direction
8. Surface Goal Force : x-Direction
9. Surface Goal Force : y-Direction
10. Table Results
CASE 2 : Angle of Attack = 2 degree
1. CAD Model
2. Velocity Cut Plot
3. Pressure Cut Plot
4. Global Goal Force : x-Direction
5. Global Goal Force : y-Direction
6. Global Goal Friction Force : x-Direction
7. Global Goal Friction Force : y-Direction
8. Surface Goal Force : x-Direction
9. Surface Goal Force : y-Direction
10. Table Results
CASE 3 : Angle of Attack = 4 degree
1. CAD Model
2. Velocity Cut Plot
3. Pressure Cut Plot
4. Global Goal Force : x-Direction
5. Global Goal Force : y-Direction
6. Global Goal Friction Force : x-Direction
7. Global Goal Friction Force : y-Direction
8. Surface Goal Force : x-Direction
9. Surface Goal Force : y-Direction
10. Table Results
CASE 4 : Angle of Attack = 6 degree
1. CAD Model
2. Velocity Cut Plot
3. Pressure Cut Plot
4. Global Goal Force : x-Direction
5. Global Goal Force : y-Direction
6. Global Goal Friction Force : x-Direction
7. Global Goal Friction Force : y-Direction
8. Surface Goal Force : x-Direction
9. Surface Goal Force : y-Direction
10. Table Results
CASE 5 : Angle of Attack = 8 degree
1. CAD Model
2. Velocity Cut Plot
3. Pressure Cut Plot
4. Global Goal Force : x-Direction
5. Global Goal Force : y-Direction
6. Global Goal Friction Force : x-Direction
7. Global Goal Friction Force : y-Direction
8. Surface Goal Force : x-Direction
9. Surface Goal Force : y-Direction
10. Table Results
CASE 6 : Angle of Attack = 10 degree
1. CAD Model
2. Velocity Cut Plot
3. Pressure Cut Plot
4. Global Goal Force : x-Direction
5. Global Goal Force : y-Direction
6. Global Goal Friction Force : x-Direction
7. Global Goal Friction Force : y-Direction
8. Surface Goal Force : x-Direction
9. Surface Goal Force : y-Direction
10. Table Results
COMPARISION PLOT OF DRAG & LIFT FORCE
| Case No. | Drag Force (N) | Lift Force (N) |
| 1. | 4.84661E-05 | -3.78885E-09 |
| 2. | 0.00014974 | 0.000922197 |
| 3. | 0.001542762 | 0.006314641 |
| 4. | 0.00346829 | 0.011802621 |
| 5. | 0.006385744 | 0.019244971 |
| 6. | 0.010353671 | 0.030034104 |
CONCLUSION :
1. Lift force linearly increase with increase in angle of attack upto critical angle of attack, after that it decrease.
2. The lift force is ZERO when angle od attack is 0 degree.
3. Drag force is also increase with increasing the angle of the attack.
4. Lift force increase with increasing the velocity of air. This shows lift force is directly propotional to inlet velocity.