Good Wind HuntingFinal Presentation: The Two-Bladed HAWT

Engineers:Andrew Fountain

Shadae Boakye-YiadomMarshall Gordon

Joe Moss

April 16, 2015

Prepared for Oor, Dean, and Airy

Overview● Lack of an established electrical grid in Guatemala● We were asked to design a small-scale wind turbine by ODA

Objectives:● Produce consistent power● Low cost● Durable● Easy to assemble● Safe

Two-bladed HAWT

Agenda● Discuss prototype design● Describe design changes● Outline budget● Analyze performance● Recommend improvements for future designs

Prototype Design

2m

0.72m2

Side viewFront view

Prototype Design

Top viewSide view

BladesInitial:● One piece● No hub● 6 cm chord length

Final:● 2 separate blades● Central hub● 10 cm chord

length

ShaftHub

Transmission● 9:4 gear ratio● Hollow shaft

Yaw SystemLazy Susan Fin

Preliminary BudgetItem Cost/

Item $Quantity Total Cost $

4in Lazy Susan 4.48 1 4.48

4in steel hose ties 1.39 3 4.17

2.5ft Steel rod shaft 5/8ths inch 5.77 1 5.77

1 meter long by 0.12 meter diameter PVC pipe 16.67 1 16.67

3”x3” Large timber rod, at least 1.5 meter long 3.97 1 3.97

Gear set 15.00 1 15.00

1 inch phillips head screws 4.37 1 4.37

Total (including 6% tax) 62.81

ItemCost/Item ($) Quantity Total Cost ($)

4in Lazy Susan 4.48 1 4.48

4in steel hose ties 1.39 3 4.17

2.5ft Steel rod shaft 1/2 inch bore 5.77 1 5.77

0.12 meter diameter PVC pipe 6.67 1 6.67

3”x3” Large timber rod (1.5m long) 3.97 1 3.97

Gear set and hubs 22.45 1 22.45

½ inch Bearings* 5.00 2 10.00

Plywood* 10.00 1 10.00

Wiring and Resistors* 1.00 1 1.00

Total Expenditure 47.51

Total* (including 6% tax) 68.71

Final Budget● Goal was < $100● We were well under

this goal● Final budget was $6

more than initial, due to gear set

● Items with * were found in the lab and not purchased

Performance Analysis

● Objectives:o Produce consistent power- inconclusiveo Low cost- meto Durable- meto Easy to assemble- meto Safe- met

Performance Analysis

● Average Voltage: 0.567 Volts● Resistance: 20 Ohms● Average Power: 0.0167 Watts

● Average Wind Speed: 2.84m/s ● Average Efficiency: 0.164%● Cut-in Speed: ~1m/s ● Tip speed ratio: 14.2

Technical Recommendations ● Optimize blades

o Use one piece for blades instead of two o Make the blades as thin as possible o Increase width of the bladeso Test to find optimal pitch angle

● Increase electrical resistance● Decrease bearing resistance● Increase sturdiness

Conclusion ● Implemented the 2-Bladed HAWT

design● Our design worked!● Met most of our objectives● Future designs should:

o Optimize bladeso Increase electrical resistanceo Use improved bearingso Increase sturdiness

“I was raised to be charming, not sincere”