Numerical Analysis of the Wing Tip Vor ces of a Commercial Aircra
XV Convergence ANSYS Mexico 2016
Ricardo Hernandez Rivera Ph.D. Student at the University of Guanajuato Mo va on
[1] Discovery Channel, Giant of the skies - Building the Airbus A380, 2006. Wing Tip Vortex Forma on
(a) Smoke flow visualiza on [2]. (b) Wing p vortex emerging at the wing p [3].
[2] J. Boehrer, CFD Study of Wing Tip Vortex Genera on, 2005. [3] J. Ber n, Aerodynamics for Engineers, 1998. Li -Induced Drag
Induced drag
Li Effec ve li
Chord line
Undisturbed free-stream Resultant velocity
[3] J. Ber n, Aerodynamics for Engineers, 1998. Descrip on
In this project, the tangen al veloci es and li -induced drags of the wing p vor ces of a commercial aircra were analyzed numerically.
Two different kinds of winglets were adapted to the original wing in order to analyze their effects on the wing p vor ces.
Objec ves
To visualize the wing p vortex forma on.
To analyze the tangen al veloci es of the p vor ces.
To evaluate the li and drag forces. 3D Modeling
Figura 7. Generación del arrastre inducido por la sustentación.
1/144 aircra plas c model of the Boeing 767-300/ER. Wing Design
Front view of the wing showing the angle of dihedral.
Wing planform. Wing Design
Geometric features of the wing.
Descrip on Variable Value
Root chord Cr 10.9 m
Root incidence angle αr 4° 15´
Tip chord Ct 2.16 m Supercri cal airfoil DFVLR R-4 of the wing root. Tip incidence angle αt 0° Sweep angle Λ 31° 30´ Dihedral angle Φ 6° Wing area S 283.3 m2 Aspect ra o AR 8 Taper ra o λ 0.1981 Wingspan b 47.4 m
Figura 7. Generación del arrastre inducido por la sustentación.Supercri cal airfoil RAE (NPL) 5212 of the wing p.
Horizontal Stabilizer
Supercritical airfoil NPL 9510 Supercritical airfoil NPL de ARC CP 1372 of the horizontal stabilizer root. of the horizontal stabilizer tip.
Ver cal Stabilizer
Symmetric supercritical airfoil NACA/LANGLEY N0011SC of the vertical stabilizer.
Engine CF6-80C2 General Electric
Geometric features of the wing.
Front view. Side View.
Figura 7. Generación del arrastre inducido por la sustentación.
Upper view. Rear view. 3D Model of the Aircra under Analysis
(b) (a)
(c) (d)
Modified commercial Boeing 767-300/ER aircra : (a) lower view; (b) isometric view; (c) lateral view; (d) front view. B747-400 Winglet
Geometric data of the B747 winglet.
Descrip on Variable Value
Root chord Cr 2.15 m
Tip chord Ct 0.88 m Sweep angle Λ 56.32° Angle with the ver cal β 33.04° Winglet area S 2.8 m2 Taper ra o λ 0.4074
Winglet span b 2.12 m
[4] h ps://commons.wikimedia.org Airbus A380 Winglet (Tip Fence)
Geometric data of the A380 winglet.
Upper part of the winglet Variable Value
Root chord Cr 1.19 m
Tip chord Ct 0.29 m Sweep angle Λ 64.34° Angle with the ver cal β 9.13° Taper ra o λ 0.25 Winglet span b 0.86 m
Lower part of the winglet Variable Value
Root chord Cr 1.19 m
Tip chord Ct 0.29 m Sweep angle Λ 57.89° Angle with the ver cal β 23.52° Taper ra o λ 0.25 Winglet span b 0.61 m
[5] h ps://en.wikipedia.org/wiki/Airbus_A380 Fluid Domain
(a) (b) Mesh Genera on
(b) (a)
(c) (d) Structured Hexa Meshing
(a) (b)
(c) Structured Hexa Meshing
(d) (e) Structured Hexa Meshing (Scan Plane)
(f)
(g) Structured Hexa Meshing (Scan Plane)
(h)
(i) Structured Hexa Meshing - B747 Winglet
(j) (k)
(l) Structured Hexa Meshing - A380 Winglet
(m) (n)
(o) Considera ons of the Analysis
Steady state. Cruise flight. Compressible flow. The aircra was considered a rigid body. Turbulence model: shear stress transport. Energy transfer model: total energy.
Number of hexahedral elements for each case studied. Descrip on Analysis Elements B767 Original aircra 1,790,631 A380 Winglet Aircra with adapta on of the A380 winglet 2,195,241
B747 Winglet Aircra with adapta on of the B747-400 winglet 2,028,975 Air Proper es
Property Value Aircra velocity 851 km/h Al tude 10.66 km (35,000 ) Mach number 0.8 Density 0.3809 kg/m3 Dynamic viscosity 1.434 x 10-5 kg/ms Temperature 218.92 K (-54.12°C) Atmosferic pressure 0.23648 atm (23.3 kPa) Speed of sound 1,068.84 km/h
Equation of state: ideal gas
Ideal gas equation of state gives good accuracy if:
air pressure (23.3 kPa) < air critic pressure (pc=3770 kPa) air temperature (218.92 K) > air critic temperature (Tc=133 K)
Boundary Condi ons
Inlet: velocity = 851 km/h. Outlet: static pressure = 0 Pa. Static temperature: 219 K.
Adiabatic walls with no slip. Adiabatic walls with free slip. Boundary Condi ons of the Engine
Outlet: static pressure = 0 Pa.
Inlet: velocity = 1,322 km/h. Inlet: velocity = 1,730 km/h. Static temperature: 214 K. Static temperature: 505 K. History of Convergence Variable Value
Accumulated Time Step
Incompressible flow: convergence criteria: 1x10-5. Compressible flow: convergence criteria: 2x10-5. Sta c Pressure (Pa) – B747 Winglet
(a) (b)
(c) (d) Sta c Pressure (Pa) – A380 Winglet
(a) (b)
(c) (d). Velocity Vectors (m/s) 2D Streamlines (m/s)
(a) 1.5 m downstream from wing tip. (b) 11.5 m downstream from wing tip.
(c) 21.5 m downstream from wing tip. (d) 31.5 m downstream from wing tip. Velocity Component “w” in Z Axis (m/s)
(a) 1.5 m downstream from wing tip. (b) 11.5 m downstream from wing tip.
(c) 21.5 m downstream from wing tip. (d) 80 m downstream from wing tip. Streamlines of the Wing Tip Vor ces (m/s)
(a)
(b) Streamlines of the Wing (m/s)
(a) Original Aircraft. (b) B747 Winglet.
(c) A380 Winglet. Maximum Tangen al Veloci es downstream of the Wing Tip Vor ces (m/s)
Original Aircra B747 Winglet A380 Winglet Velocity (m/s) (m/s) Velocity
Distance (m)
The maximum tangential velocity of an Airbus A340 for cruise speed is about 60 m/s at the wing tip [6].
[6] Adib, Interac on between the Wing Trailing Vortex and the Engine Plume, 2006. Li and Drag Forces
Aircra Wing Descrip on Drag (kN) Drag (kN) Li (kN) Es mated ϵ
Original aircra 190.00 100.70 1,651.90 2.63° Aircra with the A380 winglet 185.20 90.80 1,677.60 2.53° Aircra with the B747 winglet 183.40 87.80 1,691.50 2.48°
The drag of both wings is about 50% of the total drag of the aircraft. The lift-induced drag is about 40% of the total drag of the aircraft for cruise speed [3].
The maximum weight of the original aircraft is 175.54 ton [7]. The lift of both wings of the original aircraft is 1,651.9kN (168.38 ton), about 96% of the maximum weight.
[3] J. Ber n, Aerodynamics for Engineers, 1998. [7] h p://www.airliners.net/aircra -data/ Conclusions
Winglets reduce the pressure gradients in the wing tip. As a consequence, the strength of the vortex is slightly decreased.
The B747-400 winglet: • decrease the angle of downwash up to 5.7% • increased the lift up to 2.39% • decreased the total aircraft drag up to 3.47% • decreased the vortex core velocity up to 15.38%
The A380 winglet: • decrease the angle of downwash up to 3.8% • increased the lift up to 1.55% • decreased the total aircraft drag up to 2.52% • decreased the vortex core velocity up to 5.76%
Thanks