Analysis of Effectiveness an Airfoil with Bicamber Surface

International Journal of Engineering and Technology Volume 3 No. 5, May, 2013 

Analysis of Effectiveness an Airfoil with Bicamber Surface 

Md.Shamim Mahmud 

Department of Naval Architecture and Marine Engineering 

Bangladesh University of Engineering and Technology 

ABSTRACT 

The research provide a stable, high-efficiency, high angle of attack, airfoil. The means for accomplishing these improvements 

is a novel,bicamberd surface profile with two or more raised ridges placed laterally to fluid flow and generally running 

parallel to the leading and trailing edge.A primary objective of this research is to improve the efficiency of airfoil to obtain 

higher ratio of useful work output to energy input, thereby saving significant energy resources. This is achieved because 

bicambered surface airfoil produce greater lift and reduced drag at normal operating angle of attack. A bicamber surface 

airfoil improved ability to retain an attached boundary layer allows a lower thickness to chord profile to give performance 

comparable to thicker ,single cambered surface airfoil. The above capabilities provide extensive possibilities in design of 

high altitude aircraft where lift coefficient is low due to thin air. Flow over a short radius object must be at a greater velocity 

than flow over a long radius object. There for bicambered surface airfoil effectively lower local Reynolds number is respect 

to boundary layer development. 

This stable high angle of attack airfoil is improving aviation safety. Private aircraft accident involve wing stall. Higher attack 

angles combined with higher lift/drag ratios would enhance glide capabilities. 

A secondary objective of this research is to reduce mechanical force input requires pitch airfoils such as rotary wings, 

propeller, rotors and impeller, saving weight in the construction. The more central aerodynamic center and low or negative 

pitches moment of bicambered surface airfoils allows this objective to be fulfilled. 

For helicopter high vehicle velocities, where high maneuverability is desired, different lift and stall properties from one side 

of the aircraft to the other cause problems. The anti stall characteristics to the bicambered surface airfoil can prevent much of 

these problems and greatly enhance the maneuverability of rotary wing vehicles. 

BACKGROUND 

In the past century extensive research with single cambered aerofoil has provided numerous airfoil designs that optimize 

aerodynamic performance under given condition. For instance reduced drag can be achieved while stall performance is 

sacrificed, higher lift is possible, but usually at the expenses of increased darg.Stall performance can be improved, but lift or 

drag performance suffers. Overall performance can be improved at some angle of attack or at some Reynolds number while 

accepting reduced performance at others.In many cases aerofoil efficiency depends on the presence of camber line. The 

relation between lift and drag coefficient for non camber and camber airfoil is stated here. And for the improvement of the 

efficiency of airfoil Author introduces with a bicamber airfoil where the bicamber airfoil is most effective than camber and 

non camber airfoil. Generally the efficiency of airfoil depends on the turbulent effect which is created on trailing edge of the 

airfoil. The lift coefficient is high where the vorticity is lower and due to increase of vortecity the lift coefficient is reduced as 

well as drag coefficient is increased. Here (NACA 4412),(NACA 0012),( NACA 2412) and a bicamber model are used as a 

test case. This research exposes that bicamber profile is most effective from naca camber and non camber profile. 

Keywords: Airfoil, Mach number, STAR CCM+, ANSYS13, NACA, Lift coefficient, Drag coefficient, Bicamber, FVM, FEM 

1. METHOD OF APPROACH 

Here is used the finite volume method (FVM) to solve 

this problem..The airfoil mesh is developed by using 

commercial CFD software ANSYS ICEM CFD (version 

13.0). The numerical solutions of the governing equations 

have been found using commercial CFD software package 

STAR CCM+(version 4.04.011) for analyzing airfoil. 

Two-dimensional Finite Volume Method (FVM) has been 

applied, turbulent flow at 60 m/s free stream velocities at 

different angle of attacks are simulated. Free stream 

boundary conditions applied in this research. The 

numerical results in terms of pressure coefficient, drag 

coefficient and lift coefficient for different meshing and 

conditions have been shown either graphically or in the 

tabular form. Contour of pressure distribution have also 

ISSN: 2049-3444 © 2013 – IJET Publications UK. All rights reserved. 

569

International Journal of Engineering and Technology (IJET) – Volume 3 No. 5, May, 2013 

been displayed graphically. And finally calculate the 

structural effect of camber and bicamber airfoil by using 

FEM analysis. 

∫ 

∑ ∑ 

F D = 

L = 

C p = 

v 2 C d A 

v 2 C L A 

N face = number of faces enclosing cell 

= value of convected through face f 

= mass flux through the face 

The transport of a scalar quantity 

represented by the integral equation: 

in a continuum is 

= area of face f 

=gradient of 

at face f 

∫ ∮ ⃗ ⃗ ∮ ⃗ ∫ 

⃗= velocity vector 

⃗= surface area vector 

= diffusion coefficient for 

= gradient of 

= source of per unit volume 

The terms in this equation are, from left to right, the 

transient term, the convective flux, the diffusive flux and 

the volumetric source term. 

Discrete Form:- 

Applying the above equation to a cell-centered control 

volume for cell-0, the following is obtained: 

V = cell volume 

Bicamber’s maximum thickness is 0.12m and maximum 

thickness position is 0.16m from leading edge 

Author has taken free stream boundary condition. 

Temperature 291k 

Dynamic viscosity 4.61×10^-5 

Turbulent model, Spalart-Allmaras Turbulence 

Velocity 60 m/s 

Density of air 1.2126 kg/m^3 

Mach Number 0.1807 

2. RESULT 

Fig: Mesh of NACA 2412 profile 


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Fig: Mesh of Bicamber profile 

Fig: Trailing edge vortecity of NACA 2412 profile 


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Fig: clips edge vortecity of Bicamber profile 

Fig: Velocity distribution of Bicamber profile 

Fig: Mach Number distribution of NACA 2412 profile 


572


Fig: Mach Number distribution of Bicamber profile 

Fig: Drag Coefficient Vs Angle of Attack 


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Validation of the result by wind tunnel test data 

Fig: Lift coefficient Vs Angle of Attack 

The two graphs, red line shows the wind tunnel test result and blue line shows FVM simulation result for bicamber profile. 


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3. Model Analysis: 

Now for structural effect analysis the author is considered 3d NACA and Bicamber profile. 

Cord Length of the NACA and Bicamber Profile 1m and Wideth also 1 m. 

Material Name: 

Aluminum Alloy 6063T4 

Model type: 

Linear Elastic Isotropic 

Default failure criterion: 

Max von Mises Stress 

Yield strength: 

9e+007 N/m^2 

Tensile strength: 

1.7e+008 N/m^2 

Elastic modulus: 

6.9e+010 N/m^2 

Poisson's ratio: 0.33 

Mass density: 

2700 kg/m^3 

Shear modulus: 

2.58e+010 N/m^2 

Thermal expansion: 

2.34e-005 /Kelvin 

Fig: Stress distribution of Bicamber Profile 

Fig: Displacement of Bicamber Profile 


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Fig: Stress distribution of NACA 4412 Profile 

Profile 

name 

Bicambe 

r 

velocit 

y 

Lift 

Force 

60m/s 4908.6 

3 N 

Fig: Stress Displacement of Bicamber Profile 

Stress 

(max) 

953787 

N/m^2 

Stress 

(min) 

1189.09 

N/m^2 

Strain 

(max) 

Strain 

(min) 

Displacement 

(max) 

1.03523e-005 2.87658e-008 0.0694524 

mm 

Naca 

4412 

60m/s 4908.6 

3 N 

1.07106e+006 

N/m^2 

1708.52 

N/m^2 

1.18481e-005 3.7737e-008 0.085971 mm 


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4. COMMENTS 

This research shows how the bicamber profile acts 

perfectly in vortex condition. As angle of attack increases 

the vorticity in upper surface also increases, so the lift 

force reduces and drag force increases. In turbulent flow, 

vortex is created in the clips between the two camber of a 

bicambered foil. The lifting effect reduced by the vorticity 

is recovered by generating the lift force in 2 nd camber. 

Thus, the lesser vortex effect in bicamber profile results in 

higher lift force and lower drag force, hence increases the 

lift by drag ratio. In this research the Author finds that 

lift-drag ratio of the bicamber airfoil is higher than NACA 

profile.On the other hand, the angle of attack increases 

lift-drag ratio is inversely proportional to the angle of 

attack. And findings suggest that for same lift force, both 

maximum displacement and stress are lower for a 

bicambered foil when compared with NACA profile. 

Thus, airfoil with bicamber profile is more effective than 

NACA profile. 

ACKNOWLEDGEMENT 

The author is grateful to the University of Illinois for 

providing airfoil coordinate data . 

REFERENCES 

[1] Badran O (2008). Formulation of Two-Equation 

Turbulence Models for Turbulent Flow over a NACA 

4412 Airfoil at Angle of Attack 15 Degree, 6th 

International Colloquium on Bluff Bodies 

Aerodynamics and Applications, Milano, 20-24 July. 

[2] Douvi C. Eleni*, Tsavalos I. Athanasios and 

Margaris P. Dionissios,( 2012) “Evaluation of the 

Turbulence Models for the Simulation of the Flow 

Over a National Advisory Committee for Aeronautics 

(NACA) 0012 Airfoil”, Journal of Mechanical 

Engineering Research Vol. 4(3), pp. 100-11. 

[3] Frederick.L.Felix.(March,7,1995) “Airfoil with 

Bicamber Surface”, United State Patent Number 

5395071 

[4] S.Kandwal1 and, Dr. S. Singh(2012) "Computational 

Fluid Dynamics Study Of Fluid Flow And 

Aerodynamic Forces On An Airfoil". International 

Journal Of Engineering Research & Technology 

(IJERT) Vol. 1 Issue 7, September – 2012 .ISSN: 

2278-0181 

[5] McCroskey WJ (1987). A Critical Assessment of 

Wind Tunnel Results for the NACA 0012 Airfoil. U.S. 

Army Aviation Research and Technology Activity, 

Nasa Technical Memorandum, 42: 285-330. 

[6] Menter FR (1994). Two-Equation Eddy-Viscosity 

Turbulence Models for Engineering Applications. 

AIAA J., 32: 1598-1605 


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Analysis of Effectiveness an Airfoil with Bicamber Surface

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