Propulsion PDR #2

AAE451 – Team 3

November 11, 2003

Brian CheskoBrian HronchekTed LightDoug MousseauBrent RobbinsEmil Tchilian

2

AAE 451Team 3Team 3 Aircraft Walk Around

•Low wing – Clark Y•Tricycle Gear

•Conventional Tail – NACA 0012

•Pusher

•Wing Span = 14 ft

•A/C Length = 10 ft

Internal Pod

3

AAE 451Team 3Team 3 Method for Propulsion Selection

• Use constraint diagram and takeoff EOM to determine required engine size

• Use modified gold.m in a loop to make plots

• Pick prop pitch and diameter from gold.m results

• Show brief analysis of fuel consumption

4

AAE 451Team 3Team 3 Constraint Diagram

Aircraft Constraint Diagram

0

4

8

12

16

20

24

28

32

36

40

0 0.25 0.5 0.75 1 1.25 1.5

W/S (lbf/ft^2)

W/P

(lb

f/sh

p)

Cruise Speed

Stall Speed

Climb

T/O dist

Landing dist

Ceiling

Endurance

Minimum Structure

Minimum Power

Power Loading = 15.5 lbf/shpIf weight = 55 lbs,SHP = 3.55 hp

5

AAE 451Team 3Team 3 Takeoff EOM Integration

WDTag

W

T = ThrustD = DragRolling Friction Factor (0.05 for dry concrete)

Assumptions

• No lift to reduce effects of friction

• Max thrust occurs instantaneously

ThrustDrag + Rolling

Friction

6

AAE 451Team 3Team 3 Static vs. Forward Flight Thrust

V

bhpT p

550

Static Thrust Forward Flight Thrust

Dn

bhp

c

cT

P

T

550

n = rotation speed (rev/s)

D = Propeller diameter (ft)

V = Velocity (ft/s)

Raymer (13.17)

• Using Forward Flight Thrust leads to very large velocities at low velocities. How large?

7

AAE 451Team 3Team 3 Forward Flight Thrust vs. Time

Forward Flight Thrust reaches

~ 12,000 lbf at time = 0

8

AAE 451Team 3Team 3 Static Thrust Used for Integration

Dn

bhp

c

cT

P

T

550

• cT, cP found for each step of integration using gold.m

• gold.m updated for results from most current prop analysis (shown later in the presentation)

9

AAE 451Team 3Team 3 Takeoff Distance based on ODE

10

AAE 451Team 3Team 3 Chosen Engine• O.S. Max 1.60 FX-FI

– $714.99 w/o muffler– 3.7 BHP @ 8500 RPM– 1,800-9,000 RPM– 2.08 lbs

Ref. O.S. 1.60FX-FI Owners Manual

• Benefits of Fuel Injection» Vs non FI

– Easier starting– More stable idling– Excellent throttle response– Pressurized fuel supply does

not depend on engine orientation

– Electronic control of engine parameters

Ref. www.towerhobbies.com

11

AAE 451Team 3Team 3 Thrust vs. Horsepower

0 5 10 15 20 250

10

20

30

40

50

60

70

80

Power [hp]

Th

rust

[lb

f]

Max Thrust vs. Power for various propellers.

18

20

22

16

D = 24

P = 14

12

10

8

6

RPM = 9000 RPM = 8500

12

AAE 451Team 3Team 3 Thrust vs. Horsepower

0 5 10 15 20 250

10

20

30

40

50

60

70

80

Power [hp]

Th

rust

[lb

f]

Max Thrust vs. Power for various propellers.

18

20

22

16

D = 24

P = 14

12

10

8

6

RPM = 9000

16 x 616 x 816 x 10

18 x 618 x 8

20 x 6

Usable Props

3.7 hp

RPM = 8500

13

AAE 451Team 3Team 3 RPM vs. Efficiency

0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.752500

3000

3500

4000

4500

5000

5500

6000

6500

7000

7500

Efficiency

RP

M

RPM vs. Efficiency for various propellers.

D = 24

22

20

18

16

16

18

20

22

D = 24

P = 6 P = 6

8

10

12

14

8

10

12

14

Rotation T = 4 lbf

Cruise T = 5.6 lbf

Stall

T = 5.6 lbf

Cruise

T = 4.0 lbf

14

AAE 451Team 3Team 3

0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.752500

3000

3500

4000

4500

5000

5500

6000

6500

7000

7500

Efficiency

RP

M

RPM vs. Efficiency for various propellers.

D = 24

22

20

18

16

16

18

20

22

D = 24

P = 6 P = 6

8

10

12

14

8

10

12

14

Rotation T = 4 lbf

Cruise T = 5.6 lbf

Best Efficiency 20 x 6

RPM vs. Efficiency

Stall

T = 5.6 lbf

Cruise

T = 4.0 lbf

15

AAE 451Team 3Team 3

0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.852500

3000

3500

4000

4500

5000

5500

6000

6500

7000

7500

Power [hp]

RP

M

RPM vs. Power for various propellers.

D = 16

18

20

22

24

18

20

22

D = 24

16

P = 6

8

10

12

14

8

10

12

P = 14

6 CruiseT = 4 lbf

RotationT = 5.6 lbf

RPM vs. Power Required

Stall

T = 5.6 lbfCruise

T = 4.0 lbf

16

AAE 451Team 3Team 3

0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.852500

3000

3500

4000

4500

5000

5500

6000

6500

7000

7500

Power [hp]

RP

M

RPM vs. Power for various propellers.

D = 16

18

20

22

24

18

20

22

D = 24

16

P = 6

8

10

12

14

8

10

12

P = 14

6 CruiseT = 4 lbf

RotationT = 5.6 lbf

Low HpRequired

20 x 6

RPM vs. Power Required

Stall

T = 5.6 lbfCruise

T = 4.0 lbf

17

AAE 451Team 3Team 3 Chosen Propeller – 2 blades

• Based on carpet plots from gold.m:– RPM used (cruise) = 5350 (~63% of

8500 max HP rpm)• Pitch is 6 inches• Diameter is 20 inches• Efficiency at cruise ~ 0.66• Efficiency at stall ~ 0.47

18

AAE 451Team 3Team 3 Chosen Propeller 4-blades• Zinger 18X5 Wood Pusher Propeller

– 18 inches in diameter with 5 inch pitch– 4 blades

Ref. www.zingerpropeller.com

Conversion from 2-bladed to 4-bladed based on Zinger recommendations:

• For 2 blade to 3 blade: lower diameter only

• For 2 blade to 4 blade: lower diameter and pitch

•Therefore, we chose a 18X5 four blade instead of a 20X6 two blade

19

AAE 451Team 3Team 3 Fuel Consumption

• Fuel Consumption based on data from O.S. Engines

• O.S. Max 1.60 FX-FI uses approx. 500 mL for 11 minute flight (~1364 mL for 30 min.)

• 1364 mL ~ 0.36 gal ~ 2.2 lbf ~ 46 oz.

• This number is based on guidelines given by O.S…..our number could be slightly different

Ref. www.towerhobbies.com

20

AAE 451Team 3Team 3 Chosen Fuel Tank

• Fuel tank chosen is:– Du-Bro 50 oz. fuel tank– $11.49 from Tower

Hobbies– Located at the C.G. of

aircraft

34 ( )

8in deep

13 ( )

2in

38 ( )

8in

Ref. www.towerhobbies.com

21

AAE 451Team 3Team 3 Future Actions

• Continue working with EOM analysis

• Look for accurate HP versus RPM curves

• Continue with 4-bladed propeller code

• Search for engine closer matching the requirements

22

AAE 451Team 3Team 3 Questions?

23

AAE 451Team 3Team 3 Appendix