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A wing creates lift by imparting a downward momentum to the air flowing above and below it. The rate of change of momentum is equal to Force (Newton's 2nd law), and therefore a reaction force pushes the wing up, producing lift (Newton's 3rd law).
The imparting of this downward momentum ("downwash") to the air results from an air pressure differential above/below the wing. If you know the pressure above the wing and the pressure below the wing, and the wing area, you can calculate the lift force on the wing since Force = Pressure x Area. If you don't know the pressures, you can get a rough estimate if you know what the average air velocities are above and below the wing. A wing creating lift will have higher speed air flowing over the top of it than flowing below it. By employing Bernoulli's Principle, you can calculate a pressure difference corresponding to the difference in velocity.
Note that there is no requirement that the air molecules separating at the leading edge and flowing below the wing meet up with the same molecules that flow over the top. This is called the "equal transit time theory" and is a popular science myth that unfortunately has found it's way into flight manuals and even some undergraduate texts. However, aerodynamicists have known ever since they started doing wind tunnel testing that the air flowing over a lifting wing reaches the trailing edge sooner than the air below it. This can be explained in terms of the circulation theory, which is an advanced concept.
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What else can I help you with?
What will the shape of the airfoil effect?
The shape of an airfoil significantly influences its aerodynamic properties, including lift and drag. A cambered airfoil, with a curved upper surface and flatter lower surface, generates more lift at lower speeds compared to a symmetrical airfoil. Additionally, the angle of attack affects how effectively an airfoil can manipulate airflow, altering lift characteristics. Overall, the design and contour of the airfoil are crucial for optimizing performance in various flying conditions.
What shape is most conducive to optimizing lift?
airfoil
What is subsonic airfoil?
which airfoil must produce the lift with less than one mach number . that is called sub sonic airfoil...... Another answer would be : an airfoil designed to perform below the speed of sound.
How does the flow over an airfoil affect its lift and drag characteristics?
The flow over an airfoil affects its lift and drag characteristics by creating differences in air pressure above and below the airfoil. This pressure difference generates lift, which is the force that allows an aircraft to stay airborne. The flow also creates drag, which is the resistance that opposes the motion of the aircraft. The shape and angle of the airfoil, as well as the speed and density of the air, all play a role in determining the lift and drag forces acting on the airfoil.
When pictorially representing the lift force on an airfoil it is shown as acting at right angles to the?
The lift force on an airfoil is typically represented as acting perpendicular to the relative airflow direction. This is because lift is generated by the pressure difference between the upper and lower surfaces of the airfoil, causing a force perpendicular to the airflow.
What is the purpose of an airfoil?
An airfoil is a 2-dimensional shape that defines when built and inserted in a moving fluid will create a "Lift". The airfoil or wing can be used to turn ships or make an airplane fly.
Why do flow separates over an airfoil?
Because of a change in the angle of attack. When you exceed the critical angle of attack there is not enough wind passing over the airfoil and therefore disrupting lift, the airfoil stalls.
What are six factors that affect the amount of lift produced by an airfoil?
Airfoil shape and design Angle of attack Airfoil size (chord length) Air density Airspeed Surface roughness and cleanliness
What is an airfoil?
An airfoil is a shape that is designed to produce lift when it moves through the air. It is commonly used in the design of wings for aircraft and blades for propellers and turbines. The unique shape of the airfoil allows air to flow faster over the top surface, creating lower pressure and generating lift.
What is the difference how a helacopter creates lift and an airplane?
They both utilize airflow over an airfoil. The helicopter moves the airfoil (blade) by spinning them, as air passes around the blade it creates lift. An airplane uses thrust from the engines to push the airfoil (wings) forward through the air, the air then flowing over(lower pressure) and under them (higher pressure) produces lift.
What happens when airfoil doesn't have enough lift?
The effect is called an Aerodynamic stall
Which part of the wing produces more lift the upper part or the lower part?
Tough question to answer as asked. In normal airfoils, the top of the airfoil is thicker and curved and it is this thicker, curved section that causes the air to speed up as it flows over it. This increase in airspeed over the top of the airfoil results in a lowering of the pressure and it is that pressure differential between the top and the bottom of the airfoil that is known as lift. However, while the shape of the top of the wing is what generates lift, the force itself is applied to the lower part of the wing, hence the airfoil rises. I guess the best answer would be to say it is produced by the upper part of the airfoil and is applied to the lower part of the airfoil. Look up Bernoulli for a more detailed discussion.
