The Effects of Blade Design on the Voltage Output of an Underwater Turbine
Peeraya
S.
8th
Grade, Stone Middle School, Melbourne Florida
Teacher: Rich Regan
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Abstract: The purpose of this experiment is to determine which underwater turbine blade design will produce the most electricity. This study is significant because it can help in the future development of more efficient and hydrodynamic turbines. In doing so, much of today’s electricity can be supplied by underwater turbines, which do not cause harm to the environment. Underwater turbines are generators that are powered by the rotation of blades in a flow of water, much like submerged windmills. Pitch is the theoretical distance a propellor would travel when rotated one time–like a screw. If rotated once, it would travel a certain distance forward, depending on the angle of the blade. This study compares 5 different blade pitches: high, medium, low, high-medium, and low-medium. Since it takes more energy to turn a higher pitched blade and causes turbulence, and a more positive pitch creates lift, the researcher was convinced that the medium pitched blade would be most efficient in aiding an underwater turbine in voltage production. Under a speed of approximately 1 meter per second, the lowest blade pitch turbine produced the most electricity (an overall mean of 54.5 millivolts), and the highest blade pitch produced the least (an overall mean of 23.8 millivolts). The outcome of the experiment did not support the researcher’s hypothesis.
