Introduction

Methodology

• Geometric data collection on various winglet design (canted, blended and fenced)
• Computational design and assembly of boeing wing alongside with various wingtips using solidworks
• Run aerodynamic simulations on each prototype
• Result analysis of the prototype
• Compare the results of the three (3) prototype
• Conclusion

Description of the Model

Figure 1. Wing Geometry.

Figure 1. Wing Geometry.

Figure 2. Fenced Winglet Geometry.

Figure 2. Fenced Winglet Geometry.

Figure 3. Canted Winglet Geometry.

Figure 3. Canted Winglet Geometry.

3.2. Computational Domain

Wing model’s rectangular domain is used as shown below, below is the domain for a blended winglet design.

Figure 4. Blended Winglet In A Domain.

Figure 4. Blended Winglet In A Domain.

3.2. Mesh Generation

The mesh generated is Unstructured tetrahedral mesh because its ability to mesh easily for complex geometry and Arbitrary positions. The mesh has been refined around the aerofoil, with additional refinement around the leading and trailing edges, while the mesh in the rest of the computational domain is coarse. In addition, values for Inflation layer thickness, Inflation layer number, and base size have been defined. The meshing of the 3D computational domain is performed with the tools available for computations as well as time constraints in mind. Mesh refinement was achieved using three separate mesh refinement choices. The base size is based on the approximate cell size calculation on the wing surface. The maximum cell size is defined as the largest distance on the surface of the computational domain in the ‘Inlet' upstream region. The mesh of the computational domain is shown in below Figures.

Figure 5. Fenced Winglet Design With Mesh.

Figure 5. Fenced Winglet Design With Mesh.

3.2. Boundary Conditions and Goals

3.2.1. Boundary Conditions

After the mesh generation for the fluid flow and wing was completed, the solver performed a numerical simulation. The boundary condition, solution control parameters, and material properties were determined when the turbulence model was selected. The model was initialized with inlet values and all the parameters were specified for various attack angles. The computation for the flow parameters was then performed several times.

Figure 6. Boundary Conditions.

Figure 6. Boundary Conditions.

Figure 7. Goals And Custom Goals.

Figure 7. Goals And Custom Goals.

Density (ρ)	$1.2754kg/m^3$
Viscosity	$1.81\times {10}^{-5}kg/ms$
Mach number (M)	0.785
Pressure (P)	101325Pa
Altitude (h)	10668m

3.2.1. Goals

The goals that would be indicated in our simulation would be “coefficient of lift”, which during our simulation would be referred to as the “normal force Y” since there is no such property like coefficient of lift in SOLIDWORKS simulation. So the goals are; Coefficient of Lift (C_L), Coefficient of Drag (C_D), and the Lift-to-Drag ratio (L/D).

$${\mathrm{C}}_{\mathrm{L}}=\frac{L}{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\rho V^{2}S};{\mathrm{C}}_{\mathrm{D}}\frac{D}{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.\rho V^{2}S};\mathrm{L}/\mathrm{D}\frac{C_L}{C_D}$$

Results and Discussions

4.1. Pressure field behind wing

The calculated pressure field is shown in Figure 4a,b in a plane perpendicular to the free stream, three wing tip chord lengths below the wingtip without and with winglets. The wing tip vortex's strength and location can be seen. The vortex creates lower pressure where it generated, which suggests high local velocities, as shown in the accompanying figures. As seen in Figure 4a, a wing without a winglet creates a stronger vortex than any other wing that has a winglet, which results in a higher induced velocity and more drag.

Figure 4. (a) Pressure intensity for wing. (b) Pressure intensity for fenced winglet.

Figure 4. (a) Pressure intensity for wing. (b) Pressure intensity for fenced winglet.

Figure 8. Pressure intensity for canted winglet.

Figure 8. Pressure intensity for canted winglet.

Figure 9. Pressure intensity for blended winglet.

Figure 9. Pressure intensity for blended winglet.

4.2. Aerodynamic characteristics

Lift and drag both increases with an increase in the angle of attack. The strength of the wing tip vortices increases with increased lift, increasing the airplane's induced drag. We lessen the force of these vortices and the resulting drag by using a winglet. The performance during takeoff and landing, where this results in a reduction in required runway length, might benefit greatly from this performance enhancement. By obtaining a faster rate of ascent, these aerodynamic structures help boost climb performance.

Figure 10. Coefficient of lift to Angle of attack plot.

Figure 10. Coefficient of lift to Angle of attack plot.

Figure 11. Coefficient of drag to Angle of attack plot.

Figure 11. Coefficient of drag to Angle of attack plot.

Figure 12. Coefficient Of Lift To Angle Of Attack Plot.

Figure 12. Coefficient Of Lift To Angle Of Attack Plot.

It is observed that the coefficient of lift (C_L) increases with an angle of attack (α) as shown in Figures 4 and 5.

The result for the coefficient of drag (C_D) is slightly different, the C_D increases with an increase in angle of attack as shown in Figures 4 and 6. The course changed for aircraft wing without winglet whereby the coefficient of drag dropped from 0.018 to 0.016 at 6⁰ angle of attack, α and then rises at 9⁰ angle of attack. The case is also different for a fenced winglet, the coefficient of drag reduced from angle of attack 3⁰. This shows how efficient the fenced wingtip device is compared to other winglets.

Figures 4 and 7 shows the lift-to-drag ratio of different wingtip devices at different angle of attack. The Fenced winglet design proved to give a promising efficiency at higher angle of attack compared to other wingtip devices and wing without winglet. Increasing the angle of attack increases the lift-to-drag ratio.

Conclusion

Table of Parameters

References

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