Bernoulli's Principle and the Wing

Well we all love flying in planes from one place to another but have you ever wondered how those large vehicles stay in the air? The answer of coarse is the wings. Now that you know that wings keep a plane aloft you are probably wondering how they work. Wings keep a plane in the air because of Bernoulli's principle. In the following pages you will learn who Bernoulli was and how we can apply his principle to the wing model.

Daniel Bernoulli ( 1700 - 1782 ), son of Johann II Bernoulli, was born in the Groningen, Netherlands. At the age of 13, Daniel was sent to Basel University to study philosophy and logic. Later he obtained his master's degree in philosophy at the age of sixteen. Although Daniel was interested mainly in mathematics, his father pushed him into the medical field where he could profit the most. Again, Daniel attended Basel and other colleges around Europe where he obtained his doctorate in medicine in 1720. While studying medicine in Venice, Daniel published his first book entitled Mathematical Exercises. Daniel soon became interested in fluid flow while working with the flow of blood and blood pressure. With the help of the famous scientist Euler, Daniel published his most famous book Hydrodynamica in 1738. In this book Daniel discusses equilibrium, pressure, and speed in fluids which led to Bernoulli's principle. Read on to find out about his principle.

The Bernoulli's equation explains the how pressure and velocity are affected as liquid moves through a tube with segments of different area. The fundamental rule shown here is as the speed of a fluid increases, its pressure decreases.

Now we can apply this rule to a wing traveling through air, otherwise known as an airfoil. When an airfoil is tilted upwards the air above the airfoil travels faster than the air below the airfoil because it has a greater distance to travel. The higher velocity above the airfoil creates a drop in pressure and the lower velocity below the airfoil creates an increase in pressure. This results in a "push" from the bottom otherwise known as lift. Since the wing is also angled upward a downward push is created from the trailing edge also pushing the airfoil upward. All of this allows a plane to fly. More efficient designs in wings have been made to allow maximum lift for different types of planes.