1. Revolutionary Technologies Group C1 Nicholas Arch, Nicholas Fraser, Robert Huth, Patrick Noble, Michael Toomey Preliminary Design Review February 21, 2008

2. Last Week’s Action Items  ITEM 1: Perform Research for Trade Studies Arch – Matlab code examines generator-gearbox features Frasier – Designing base “tower” and guy wires Huth – Modeling loads on shaft to determine diameter and material properties needed Toomey – Calculated area required to extract necessary power from wind and number of blades in helix Noble – Research methods for analyzing fluid flow through blade overlap

3. Item 1: Trade Studies in Progress T=(D 1 -D 2 )r=ρdV 2 (A 1 C d1 -A 2 C d2 )/16 d D1D1 D2D2 A1A1 A2A2

4. Item 1: Trade Studies (Cont’d) For a hollow shaft, deflection is more dependent on outer diameter. Plot will allow material selection (Elastic modulus) for a maximum deflection. Elastic Modulus [Gpa] Max. Deflection [m]

5. Last Week’s Action Items (Cont’d)  ITEM 2: Develop Intelligent Systems Concepts for Turbine As group, brainstormed concepts:  Monitor rpm of turbine and generator shafts with tachometers  Anemometer to measure wind speed Discussed electronic components with Mr. Brownell  Battery type (Lithium-Ion, Carbon-Zinc, Capacitor, Lead Acid)  Charging issues (Diode, Voltage Regulator, DC-to-DC Converter)  Safety concerns (Temperature Sensor – Relay Control System)

6.  Lead Acid Battery Chosen – simple charging scheme and produces fairly constant 12.6 V  Current Regulator Required (i.e. diode, automotive V-regulator, DC-to-DC converter)  Safety Concerns Cutout charging if charging current or temperature is too great Cutout generator or brake turbine if outside operating zone Item 2: Electronics light relay Reg. Gen. 1.8 A 3.6 A

7. Current Status of Concept Status of Design - Trade Studies to assist in critical decision-making - Show-stopper: Simple, quick to assemble

8. Next Week’s Action Items  Major Component Selection and Ordering Huth will present shaft study results and group will determine shaft to order (Tues. 2/26) Investigate bearings to fit shaft (Tues. 2/26) Arch will search for gears (Tues. 2/26) Noble will check back with Mr. Brownell to ensure generator procurement (Tues. 2/26) Select and locate blade material (Huth will visit Physics machine shop) (Thurs. 2/28)

9. Next Week’s Action Items Cont’d  Complete Trade Studies Group members will present results from trade studies (Thurs. 2/26) Critical design variables selected (Thurs. 2/26):  Blade Diameter and Height  Overlap Gap  Number of Blades  Total Prototype Height  Base Diameter and Support System  Gear Ratio

10. Thank You Questions?