The Drag Coefficients of Boats

The purpose of our experiment was to determine the drag coefficient of differently shaped boat hulls made from foam insulation that had the same cross-sectional area. One of our three hulls was a rectangular hull, another was a triangular hull, and the last hull was parabolic in shape. To measure the drag coefficient of the objects we used a water tank and measured how much time it took a mass attached to the hulls to pass through two timing gates. From the time we could determine the drag coefficient of each of the objects using the drag equation. The results of our experiment showed that there was direct relationship between the shape of an object and its drag coefficient. The parabolic hull had a lower coefficient of drag because it was more hydrodynamic. This would result in less friction between the water and the hull, and therefore a lower drag coefficient. Finding the drag coefficient of any object is useful to engineers of all types of vehicles like planes, boats, and cars. Boat manufacturers often use the drag coefficient and drag forces to determine how hydrodynamic a boat is so that it serves a particular purpose like a cruise ship or a speed boat. Testing the hulls in the pool of water is helpful because it shows how they perform in a controlled situation.

Research Done By:

Richard Elia
Sterling Heights High School

Nebu Mathew
Sterling Heights High School