Aerodynamics 1 QDR Aether Aerospace AAE 451 September

Aerodynamics 1 QDR Aether Aerospace AAE 451 September 27, 2006 Mark Davis Hank Kneitz Joshua Rodewald Mathieu Hautier Ashley Gordon Ryan Mulligan Brandon Wampler Samantha Pearcy

Overview n Aircraft Geometry ¡ n Airfoil Selection ¡ ¡ n n n ¡ ¡ n Aspect Ratio Wing and tail geometry Aircraft wetted area Aerodynamic Mathematical Model ¡ n Wing Tail Aerodynamic Trade Study ¡ n 3 -view Lift Coefficient Drag Polar Moment Coefficient Aircraft Trim Diagram Future Work 16 September 2020 AAE 451, Aether Aerospace 2

Aircraft Geometry 5. 26 ft 1. 59 ft 4. 0 ft 16 September 2020 AAE 451, Aether Aerospace 3

Aerodynamic Design Point n Max speed at steady, level flight ¡ ¡ ¡ n α = 0º V = 125 ft/s (~85 mph) Sea level From vehicle sizing ¡ ¡ ¡ W = 5. 5 ft S = 3. 25 ft 2 (W/S) = 1. 7 lb/ft 2 16 September 2020 AAE 451, Aether Aerospace 4

Wing Airfoil Selection n MH-24 Characteristics ¡ ¡ ¡ n MH-32 Characteristics ¡ ¡ n Requires very precise manufacturing Designed for Re ~ 800 k Used on piston-engine pylon racer Higher CLmax Designed for Re < 500 k Wind tunnel data for Re = 300 k Used on electric powered pylon racers Selecting the MH-32 airfoil for the wing 16 September 2020 AAE 451, Aether Aerospace 5

Wing Airfoil Section – MH 32 16 September 2020 AAE 451, Aether Aerospace 6

Tail Airfoil Section n NACA 0009 ¡ ¡ Symmetric Low t/c 16 September 2020 AAE 451, Aether Aerospace 7

Aspect Ratio Trade Study n Optimize AR for minimum total drag (Cd 0 + Cdi = Cd) n Assumes turbulent flow Increasing Cdo 16 September 2020 AAE 451, Aether Aerospace 8

Aspect Ratio Trade Study n Optimize AR for minimum total drag (Cd 0 + Cdi = Cd) n Decreasing Cdi 16 September 2020 AAE 451, Aether Aerospace 9

Aspect Ratio Trade Study n Results ¡ ¡ ¡ n ARopt = 8. 5 Cd, min = 0. 0175 (Cf ~. 0057) Solution depends on: ¡ Velocity n ¡ Optimum AR = 8. 5 Inversely proportional Weight n Directly proportional 16 September 2020 AAE 451, Aether Aerospace 10

Wing Geometry Wing Airfoil MH 32 S 3. 25 ft 2 Aspect Ratio Span Taper Ratio 8. 5 5. 26 ft 0° Quarter Chord Sweep -2. 56° Trailing Edge Sweep -10. 12° 16 September 2020 2. 56° Leading Edge 0. 38 ft 0. 85 ft 10. 12° 0. 45 Leading Edge Sweep Dihedral Quarter chord line 2. 63 ft yes AAE 451, Aether Aerospace 11

Fuselage Design n Ongoing Fuselage Trade Study ¡ ¡ ¡ n Minimize Weight Sufficient Tail size Sufficient Control Surface Size Future Considerations: ¡ ¡ Minimum build-able fuselage length Weight and size for control surfaces at each fuselage length 16 September 2020 AAE 451, Aether Aerospace 12

Tail Geometry Design Process n Calculate required tail areas n Tail size coefficients for proper control size ¡ ¡ n n c. HT = 0. 5 c. VT = 0. 04 SVT = 0. 285 ft 2 SHT = 0. 49 ft 2 16 September 2020 AAE 451, Aether Aerospace 13

Tail Geometry Design Process n V-Tail consideration ¡ ¡ ¡ n V-tail requires same total tail area as conventional configuration Stails = 0. 78 ft 2 (total - conventional) Sv-tail = 0. 39 ft 2 per tail Dihedral angle ¡ 37. 3º 16 September 2020 AAE 451, Aether Aerospace 14

Tail Geometry V-Tail Airfoil S NACA 0009 0. 39 Aspect Ratio Span ft 2 - each 3. 25 1. 59 ft Taper Ratio 0. 45 Leading Edge Sweep 25° Quarter Chord Sweep 12. 7° Trailing Edge Sweep 0° Dihedral 16 September 2020 Quarter chord line Lead ing E 25° dge 0. 67 ft 0. 3 ft 0. 795 ft 12. 7° -35° AAE 451, Aether Aerospace 15

Aircraft Wetted Area n Use CATIA function to find an accurate wetted area 16 September 2020 AAE 451, Aether Aerospace 16

Aircraft Drag Polar n Cfe = 0. 005 ¡ n Historical data from Raymer CDo = 0. 032 16 September 2020 n n e = 0. 797 k = 0. 047 AAE 451, Aether Aerospace 17

Aircraft Drag Polar n 16 September 2020 AAE 451, Aether Aerospace Note a marked reduction in CD 0. Changes in wing and tail geometry were contributing factors, however the streamlining of the fuselage accounts for the greatest drag reduction. 18

Moment Coefficient n CMo = -0. 068 ¡ From XFOIL 16 September 2020 n CMa = 0. 1432 ¡ AAE 451, Aether Aerospace From XFOIL 19

Aircraft Lift Curve n n n From wind tunnel data & XFOIL Raymer “ 90% est” ¡ ¡ n ¡ Clo = 0. 293 (2 -D) ¡ Cla = 5. 6936 0 2 -D to 3 -D CLo = 0. 9 Clo CLo = 0. 2632 (3 -D) 16 September 2020 n CLa = 5. 575 AAE 451, Aether Aerospace 20

Lift Coefficient Curve *a in radians 16 September 2020 AAE 451, Aether Aerospace 21

Drag Polar and Lift Curve with Flaps Near 1. 6 design point 16 September 2020 AAE 451, Aether Aerospace 22

Maximum Lift Coefficient, MH-24 n Clmax = 1. 12 ¡ n n XFOIL data: 2 -D from online data CLmax = 1. 08 CLmax, flaps = 1. 5 16 September 2020 AAE 451, Aether Aerospace 23

Future Work n Fluent CFD Model ¡ ¡ n Purpose ¡ ¡ ¡ n Entire aircraft Separate tail/wing models Better structural loading analysis Better aerodynamic model for D&C Identify/correct areas of high drag Status ¡ ¡ ¡ Mesh complete but needs refinement Will be able to run solution Can be modified for flaps 16 September 2020 AAE 451, Aether Aerospace 24

Future Work n Continue Integrating code ¡ ¡ ¡ Ensures global usage of parameters Integrates aerodynamics, controls, propulsions and structures Integrates trade study codes 16 September 2020 AAE 451, Aether Aerospace Sa mp le O utp ut 25

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Wing/Tail Geometry Equations n Span n Root chord n Tip chord n TE sweep n c/4 sweep 16 September 2020 AAE 451, Aether Aerospace 27