Ashley Brawner Neelam Datta Xing Huang Jesse Jones Aerodynamics PDR 2 Team 2: Balsa to the Wall Ashley Brawner Neelam Datta Xing Huang Jesse Jones Matt Negilski Mike Palumbo Chris Selby Tara Trafton

Overview Design Point Airfoil Selection Component Drag Buildup Drag Polar AR trade study (CL)max Approximation (Cl)max method (CL)max Raymer method Flap analysis

The Design Point 5.5 [lbs] Weight 0° Dihedral Angle 110 [ft/sec] Speed Planform area based on approximated (CL)max and weight estimate Dihedral angle of 0° taken from Roskam Design speed decreased from 150 ft/sec Designed to high speed mission Weight 5.5 [lbs] Dihedral Angle 0° Speed 110 [ft/sec] Horizontal Tail Span 1.5 [ft]

Airfoil Selection: Main Wing Wing Section NACA 1408 Gives approximate 2D Cl needed for dash Relatively thin for minimizing drag Thick enough for structural strength

Airfoil Selection: Tail Tail Sections Horizontal Stabilizer Symmetric with low Cd over a wider range of a.o.a. compared to other similar airfoils Symmetric Jones airfoil (≈8% t/c) Vertical Stabilizer NACA 0006

Drag Build-up Method (Raymer) Cfc = Component skin friction coefficient FFc = Component form factor Qc = Component interference effects Swet,c = Component wetted area Sref = Wing planform

Component Coefficient of friction

Drag Build-up Method results Inputs:

Drag Polar

AR Trade study

AR Trade study

(Cl)max Approximation Compare XFOIL with Abbott & Doenhoff wind tunnel data Conclusion αClmax ≈ 0.8αClmax(XFOIL)

Flap analysis Ads Use (CL)max approximation from Raymer Use XFOIL to find (Cl)max with flaps Observation - Flapped (Cl)max follows linear trend Determine maximum achievable (CL)max Find flap configuration that acheives optimal (CL)max

Flap analysis: (continued) Use linear fit lines to find a Δ(Cl)max and then find Δ(CL)max with the following equation from Raymer: ads The ratio blank is based on the intial sizing of the wing area and tail span and is assumed to remain constant

Flap Geometry: flap hinge location (x/c) = 0.8 maximum flap deflection = 35° constant (cf/c) flap (CL)max (w/ flaps) = 1.06 (Cl)max (w/o flaps) = 0.85

Summary Table (CL)max (w/ flaps) 1.06 (CL)max (w/o flaps) 0.84 CD0 0.0253 AR 6 b 5 [ft] croot 16.24 [in] ctip 7.35 [in] troot 1.3 [in] ttip 0.6 [in] Flap location (x/c) 0.8 Maximum flap deflection 35°

Questions?