John Wloch Wind-Aid Preliminary Design Review 11 March 2008

Current Status – On Schedule Individual Trade Studies Completed and Uploaded to website Ordered/Acquired most components for prototype Generator, Blades, Batteries, Base Materials Tower Materials DC-DC Converter/Voltage Regulator Wind-Aid Show Stoppers: None at this time We are on schedule, per group and class project timetables

Trade Study Decisions Twist angle of blade along length is optimized, as well as blade length Generator has been selected and optimum input conditions determined, considered Tower segments will be Al, Schedule 5S; 4, 3, and 2.5 in. Base with 130 lbs can resist a 45 mph wind Wind-Aid

Next Week Action Items: Assemble Base Flowchart for Microcontroller Coding Finalize Tower Design and Acquire Materials Wind-Aid

Questions?

Wind-Aid Max Stress on Blade vs SolidityTotal Weight of Blades (3) vs Length Blade Sizing and Material Selection Ideal Length for 25 W at 12 mph wind speed is 28 inches Ideal Material based on strength and weight considerations is Carbon Fiber

Wind-Aid Blade Shaping Twist angle of blade along length is optimized. Optimized for wind speed of 12 mph and generator speed of 500 rpm

Results of the Trade Study: Steel is too heavy to use PVC pipe is not rigid enough A bigger tower geometry is needed to use aluminum as tower material Tower Wind-Aid Nominal Diameter (in) Outer Diameter (in) Inner Diameter (in) SCHEDULE: 5S Weight = 8.65 lbs. Material = Aluminum Its total deformation is 0.14 in.

Wind-Aid Base weight was varied from lbs A 130 lb base can resist a max. 45 mph wind Base Stability

Previous Concept Sketch Wind-Aid