PDR: 2/22/08PDR: 2/22/08

Pinwheel Technologies (C3)Pinwheel Technologies (C3)Heather BlahaHeather Blaha

Matt FuxaMatt FuxaJoey KingJoey King

Michael McConnellMichael McConnellDomenic TassoniDomenic Tassoni

Recap

Vertical Wind Turbine Drag Based

Action ItemsAction Items

Prototype RequirementsPrototype Requirements Is it feasible?Is it feasible? Is it relevant?Is it relevant?

Turbine Blade GeometryTurbine Blade Geometry HeightHeight WidthWidth CurvatureCurvature

Prototype RequirementsPrototype Requirements

SpinsSpins PortablePortable

No part over 4’No part over 4’ <50 lbs<50 lbs

StableStable Interchangeable ShaftInterchangeable Shaft Set-up TimeSet-up Time

2 people, 15 min2 people, 15 min

Electrical OutputElectrical Output Satisfies power Satisfies power

requirementrequirement

Multiple Speed Multiple Speed ConditionsConditions

Low and High WindLow and High Wind

Energy StorageEnergy Storage BatteryBattery

Embedded IntelligenceEmbedded Intelligence Current routed from a full Current routed from a full

battery to resistive heater.battery to resistive heater.

Width of TurbineWidth of TurbineMoment of inertia Moment of inertia

increases exponentially increases exponentially with width.with width.Wind energy function Wind energy function of area, increases of area, increases linearly.linearly.Conclusion: Pick a Conclusion: Pick a width and vary height to width and vary height to satisfy requirements.satisfy requirements.Width of 0.75 meters Width of 0.75 meters decided upon.decided upon.

Height of TurbineHeight of TurbineIncreased height Increased height increases wind energy, increases wind energy, decreases stability.decreases stability.Calculations based on Calculations based on summing moments summing moments around back edge of around back edge of base.base. 3.5’ confirmed height.3.5’ confirmed height.Stability increased by Stability increased by widening basewidening base

Wind Velocity (mph)

Max Blade Height (m)

30 0.924

29 0.972

28 1.008

27 1.068

26 1.116

25 1.176

24 1.2

Blade CurvatureBlade CurvatureSemi-cylindrical bladesSemi-cylindrical bladesEfficiency declines as Efficiency declines as the radius of the blade is the radius of the blade is increased.increased.Blades greater than a Blades greater than a certain radius are not certain radius are not feasible (negative feasible (negative efficiency!)efficiency!)

Current StatusCurrent Status

Trade Studies CompleteTrade Studies CompleteGroup Discussion of All StudiesGroup Discussion of All StudiesTurbine BladesTurbine Blades

Width, Height, CurvatureWidth, Height, Curvature

Drive ShaftsDrive ShaftsDimensions, InterchangeableDimensions, Interchangeable

On-schedule - No “Show Stoppers”On-schedule - No “Show Stoppers”

Next Week’s Action ItemsNext Week’s Action Items

Order/Procure Key PartsOrder/Procure Key PartsAluminum for blades.Aluminum for blades.Shafts and bearings.Shafts and bearings.HDPE for end caps.HDPE for end caps.Obtain battery locally.Obtain battery locally.Look into scrap aluminum for base.Look into scrap aluminum for base.

Detailed CAD ModelDetailed CAD ModelFully illustrates key concept features.Fully illustrates key concept features. Incorporate calculated dimensions.Incorporate calculated dimensions.

Questions?Questions?