October 7, 2003 Propulsion PDR 1

Team 5 Propulsion PDRTeam 5 Propulsion PDR

• Scott Bird• Mike Downes• Kelby Haase• Grant Hile• Cyrus Sigari• Sarah Umberger• Jen Watson

October 7, 2003 Propulsion PDR 2

PreviewPreview

• Engine Selection

• Propeller Sizing

• Manufactured Choice

October 7, 2003 Propulsion PDR 3

Constraining ConditionsConstraining Conditions

• SHPconstraint = 4.08

• SHPdesign=5.0

October 7, 2003 Propulsion PDR 4

Preliminary Choice for EnginePreliminary Choice for Engine

• BME-50

• Power = 5.0hp

• RPM: 1200-10,000

• Weight = 3.25 lbs.

October 7, 2003 Propulsion PDR 5

Propeller SizingPropeller Sizing

• Used modified gold.m code

• Varied Pitch and Propeller Diameter

• Assume RPM = 7000

• Assume Velocity = 50 ft/s

http://www.danspropshop.com/pitch.html

October 7, 2003 Propulsion PDR 6

Propeller SizingPropeller Sizing

• Coefficient of Thrust vs. Advance Ratio

October 7, 2003 Propulsion PDR 7

Propeller SizingPropeller Sizing

• Coefficient of Power vs. Advance Ratio

October 7, 2003 Propulsion PDR 8

Propeller SizingPropeller Sizing

• Efficiency vs. Advance Ratio

October 7, 2003 Propulsion PDR 9

Propeller SizingPropeller Sizing

• Efficiency vs. Power Output

Blue: Increasing Pitch

Black: Increasing Diameter

October 7, 2003 Propulsion PDR 10

Propeller SizingPropeller Sizing

• Efficiency vs. Power Output

Diameter = 25”

Pitch = 6”

October 7, 2003 Propulsion PDR 11

Propeller SizingPropeller Sizing

• Efficiency vs. Power Output at 7000RPM

• Pitch = 6 in.• Diameter = 25 in.• J = 0.2057/rev• η = 51%• Power = 4.71 hp

• CT = 0.034

• CP = 0.0139

• Velocity = 50 ft/s

October 7, 2003 Propulsion PDR 12

Propeller SizingPropeller Sizing

• Used second modification of gold.m code

• Held Pitch constant at 6 inches and Diameter constant at 25 inches

• Assume Velocity = 50 ft/s

• Varied RPM

October 7, 2003 Propulsion PDR 13

Propeller SizingPropeller Sizing

• Efficiency vs. Advance Ratio

October 7, 2003 Propulsion PDR 14

Propeller SizingPropeller Sizing

• Coefficient of Thrust vs. Advance Ratio

October 7, 2003 Propulsion PDR 15

Propeller SizingPropeller Sizing

• Coefficient of Power vs. Advance Ratio

October 7, 2003 Propulsion PDR 16

Propeller SizingPropeller Sizing

• Maximum Efficiency at Cruise is 3800 RPM

• At Maximum Efficiency of Cruise – CT = 0. 0145

• At Maximum Efficiency – CP = 0.0078

October 7, 2003 Propulsion PDR 17

Propeller SelectionPropeller Selection

• Chose propeller from available stock at www.BMEengines.com

• Comparison of available propellers to Efficiency graph, chose a 22 in. X 8 in. propeller

October 7, 2003 Propulsion PDR 18

Propeller SelectionPropeller Selection

• New Propeller – 22 in. X 8 in.• At 7000 RPM

– J = 0.234

– CP = 0.022

– CT = 0.048

– η = 50%

• At Cruise, best RPM = 3300

October 7, 2003 Propulsion PDR 19

Summary Summary

• Diameter of propeller = 22 inches• Pitch of propeller = 8 inches• Efficiency of propeller = 50%

• Still to Come– Geometric Properties such as airfoil section, twist

distribution, chord distribution and shape

– Trade studies of effect of AR and CLmax on Power Loading

October 7, 2003 Propulsion PDR 20

QuestionsQuestions

• Questions??

October 7, 2003 Propulsion PDR 21

Engine StudyEngine Study

Power Output vs. Weight

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0 1 2 3 4 5 6 7

Weight (lbs)

Pow

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utpu

t (hp

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