Transcript Heavy Lift Cargo Plane - Stevens Institute of Technology

Heavy Lift Cargo Plane
December 9th, 2004
Group #1
Matthew Chin, Aaron Dickerson
Brett J. Ulrich, Tzvee Wood
Advisor: Professor Siva Thangam
Overview
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SAE Aero Design Rules
Conceptual Design
– Design Matrix
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Materials
Budget
Boom
Wing Selection
– Previous Designs
– Features
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Landing Gear
FEM Analysis
EES Calculations
Tail Plane Calculations
Team Dynamics & Conclusion
Design Concepts
&
Materials Selection
SAE Aero Design Rules
• For Regular Class:
– Wing Span Limit – maximum width of 60 inches
– Payload Bay Limit – 5” x 6” x 8”
– Engine Requirements
single, unmodified O.S. 0.61FX with E-4010 Muffler
– Take off time limited to a max of 5 minutes
– Maximum takeoff distance of 200 ft and landing
distance of 400 ft
• Aero East Competition
– Date: April 8–10
– Location: Orlando, Florida
Conceptual Design (recap)
• Reviewed past design entries
• Considered:
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Flying wing
Monoplane
Bi-plane
Two sequential wings
• Design alternatives were evaluated for
performance, feasibility, and cost.
Design Decision Matrix
Materials
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Balsa wood
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Plywood
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Composite material
Stronger and lighter than other metals
Reinforce wings with rods
Aluminum
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Stronger than balsa wood
Used in construction for wing
Will reinforce dihedral design
Carbon fiber
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Ease of use
Used in rib manufacture
Fuselage
Engine bracket
Landing Gear
Thermal Monocot
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Reduce parasitic losses on wings
Projected Budget
Wing Selection
&
Boom Design
Previous Wing Selection
• Selected for competition in:
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2000: Eppler 211
2001: Eppler 423
2002: OAF 102
2003: Selig 1223
• Our selection:
– Eppler 423
– High coefficient of lift
Camber
0.0992
Trailing edge angle[deg]
7.5231
Thickness
0.1252
Leading edge radius
0.0265
Wing Features
• Eppler 423 - a subsonic high lift airfoil
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Camber 0.0992
Trailing edge angle 7.523°
Thickness 0.1252
Leading edge radius 0.0265
From XFOIL
Based on unit Chord
• Dihedral
– Angle of 3.5°
– 2” at ends
(http://www.colorado-research.com/~gourlay/dome/hiFreq/)
• Horner Plate
– ½” larger than thickness in one direction
– 10% increase to the area of rib
(http://www.rcuniverse.com/forum/Tip_Plates/m_2282825/tm.htm)
Main Wing
• Previous structural weakness
• Model currently too complex for COSMOS to
mesh
Symmetric model for FEM analysis
22.5 lb on lower surface
fixed face
Boom
• Balsa sheets versus Carbon Fiber rods
Chose Balsa sheets from reasons stated above
• Taper
– More Aerodynamic
– Less Mass
– Sleek design
FEM Analysis
Landing Gear
&
Engine Mount
Landing Gear
• Weakness in past years – strength is a priority
• Tricycle design: focus on main rear wheels
– Aluminum 6061
– Parabolic spring (actually elliptical in shape)
http://www.ticonsole.nl/parts/springs/what.htm
Engine Mounting
• Aluminum 6061
• Mount for engine, secures to front face of fuselage (backing
plate to be used with through bolts)
Engine/Muffler 23.6 oz
EES Takeoff Calculations
• Method derived from fluid mechanics text and
Nicolai’s ‘white paper’
• Calculates take-off distance by two methods
→ yielding similar results
• Key Inputs
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Weight (max) = 45lb
Fuselage length = 15”
Fuselage width = 6.5”
Boom length = 34”
Wingspan = 60”
Wing AR = 3
• Key Outputs
– Vtakeoff ≈ 39 mph
– Takeoff distance ≈ 60’
• Other Outputs (sample)
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Thrust (@Vtakeoff) ≈ 45 lb
Drag ≈ 5 lb
Various Reynolds numbers
Area projected
Tail Plane Calculations
Tail Plane Function
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Aircraft control
Stabilize aircraft pitch
Small tail plane results in instability
Extra large tail plane increases drag
Tail Plane Size
• Offsets all moments generated in flight
– Lift/Drag forces on primary airfoil
– Pitching moment of primary airfoil about its
aerodynamic center
– Pitching moment of airflow around fuselage
– Pitching moment of tailplane
– Lift/Drag forces on tail plane
• Tail drag force and pitching
moment are negligible
Tail Plane Size
• Analysis generalized
• Lift/Drag forces
resolved to act
normal/parallel to
airplane reference line
• Moments all taken
about center of gravity
• Moments all converted
to “coefficient” form
N  L cos  iw   D sin  iw 
C  D cos  iw   L sin  iw 
M cg  Nxa  Cz a  M ac  M fus,nac  N t lt
M / qcSW = CM
Tail Plane Size
Cl vs Angle of Attack
2
1.8
1.6
1.4
1.2
Cl
• Profili Software utilized
for lift/drag/moment
coefficients
• Lift coefficient of
primary airfoil
(Eppler 423)
determined as a
function of attack angle
• CD = f(CL)
• CM = f(α) ≈ -0.2
y = -1.170E-05x4 + 5.367E-05x3 - 1.289E-03x2 + 1.019E-01x + 1.082E+00
R2 = 9.999E-01
1
0.8
0.6
0.4
0.2
0
-10
-5
0
5
Angle of Attack
10
15
20
Tail Plane Size
• Downwash from primary foil
effects tailplane
(NACA 0012)
• Lift coefficients determined
with Profili
• Pitching moment of the
fuselage depended upon:
– Change in airfoil pitching
moment with respect to
angle of attack
– Change in lift coefficient
with respect to angle of
attack
– Fuselage “fineness ratio”
Tail Plane Size
• Mathematical model for
tail plane size entered
into EES
• Final tail plane
minimum planform
area: 183.4 in2
• Rule of thumb: Tail area
is 15-20% of wing area
• Wing is 1200 in2
The Wrap Up
Chosen Design
Final Design
Various Unused Features
Team Dynamics
• Learned how difficult team work can be
• In fighting over who was in charge often
resulted in wasting of time
• Personality conflicts occasionally made
working environment difficult
• Ultimately produced quality work
Concluding Remarks
• Selected foils:
– Main Wing: Eppler 423
– Tail Wing: NACA 0012
• Preliminary calculations estimate a lifting
capacity of 30 lbs
• Plane ready for construction
• Expect minor refinements over the coming
weeks subject to completion of add’l FEA tests
Your Feedback is Appreciated
Group #1
Matthew Chin, Aaron Dickerson
Brett J. Ulrich, Tzvee Wood
Advisor: Professor Siva Thangam