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Heavy Lift Cargo Plane. December 9 th , 2004. Group #1 Matthew Chin, Aaron Dickerson Brett J. Ulrich, Tzvee Wood Advisor: Professor Siva Thangam. Overview. SAE Aero Design Rules Conceptual Design Design Matrix Materials Budget Boom Wing Selection Previous Designs Features
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Heavy Lift Cargo Plane December 9th, 2004 Group #1 Matthew Chin, Aaron Dickerson Brett J. Ulrich, Tzvee Wood Advisor: Professor Siva Thangam
Overview • SAE Aero Design Rules • Conceptual Design • Design Matrix • Materials • Budget • Boom • Wing Selection • Previous Designs • Features • Landing Gear • FEM Analysis • EES Calculations • Tail Plane Calculations • Team Dynamics & Conclusion
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: • Flying wing • Monoplane • Bi-plane • Two sequential wings • Design alternatives were evaluated for performance, feasibility, and cost.
Materials • Balsa wood • Ease of use • Used in rib manufacture • Fuselage • Plywood • Stronger than balsa wood • Used in construction for wing • Will reinforce dihedral design • Carbon fiber • Composite material • Stronger and lighter than other metals • Reinforce wings with rods • Aluminum • Engine bracket • Landing Gear • Thermal Monocot • Reduce parasitic losses on wings
Previous Wing Selection • Selected for competition in: • 2000: Eppler 211 • 2001: Eppler 423 • 2002: OAF 102 • 2003: Selig 1223 • Our selection: • Eppler 423 • High coefficient of lift
Wing Features • Eppler 423 - a subsonic high lift airfoil • Camber 0.0992 • Trailing edge angle 7.523° From XFOIL • Thickness 0.1252 • Leading edge radius 0.0265 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)
Symmetric model for FEM analysis 22.5 lb on lower surface fixed face Main Wing • Previous structural weakness • Model currently too complex for COSMOS to mesh
Boom • Balsa sheets versus Carbon Fiber rods Chose Balsa sheets from reasons stated above • Taper • More Aerodynamic • Less Mass • Sleek design
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/Muffler 23.6 oz Engine Mounting • Aluminum 6061 • Mount for engine, secures to front face of fuselage (backing plate to be used with through bolts)
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 • 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) • Thrust (@Vtakeoff) ≈ 45 lb • Drag ≈ 5 lb • Various Reynolds numbers • Area projected
Tail Plane Function • 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 • Moments all taken about center of gravity • Lift/Drag forces resolved to act normal/parallel to airplane reference line • Moments all converted to “coefficient” form M / qcSW = CM
Tail Plane Size • 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
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
Final Design Various Unused Features Chosen Design
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