One of the large projects of the annual Introduction to STEM course taught to first-year students is a competition to design and fabricate the most efficient propeller blade. Course teacher Jesse Jackson introduces the students to some basic concepts related to aeronautic design and then turns the students loose to research, design and fabricate their masterpiece. The most efficient propellor is measured by connecting the blades to a small generator tower that then uses an Arduino based system to measure total electrical output.
This years' winning team, Sina Abraham (Cambridge, MA); Lindsey Gould (Sharon, MA); and Nicholas Kim (San Francisco, CA) said they followed a standard engineering protocol to achieve their result. They did research, studied both successful and unsuccessful prior year designs, and built a couple of iterations of the design. Concerning the design piece, all of the student teams used Solidworks, a very advanced CAD design program, starting with a blade template. The winning team altered the angle of the blade along its length beginning (from the attachment point) with a 25-degree angle, and tapering to a 20-, 17- and 14-degree angle toward the tip. Based on their observations, they believed that the angle of attack needed to be steepest near the hub and wanted to create a "belly" at that point.