NACA 0012 Airfoil (Compressible Flow) CFD Simulation, ANSYS Fluent Tutorial

This simulation is about NACA 0012 airfoil via ANSYS Fluent software. We perform this CFD project and investigate it by CFD analysis.

In general, the airfoil is the same as the plane's wing cross-section, wind turbine blade, helicopter, and so on. However, it should be noted that different airfoils can be used to construct an aircraft wing, and the choice of airfoil type in different applications depends on the aerodynamic characteristics.

Geometric defining parameters include chord line, angle of attack, leading edge, and trailing edge. The direction of the airflow into the airfoil is defined by the angle of attack (the angle between the chord and the horizontal direction of the airflow velocity).

In the present case, the attack angle is 5 degrees; thus, the horizontal component of the airflow direction is defined as 0.996 (cos5), and the vertical component is equal to 0.087 (sin5).

This project aims to investigate the airflow behavior and the pressure distribution around the airfoil and study the drag and lift forces.

We design the geometry of the present model by Design Modeler software. We mesh the model with ANSYS Meshing software. The model mesh is structured, and 35000 cells have been created.

Airfoil Methodology

In this simulation, the density-based solver is performed because the airflow is considered compressible.

Defining the Mach number in the boundary conditions is necessary for compressible flows. The Mach number is equal to the ratio of the speed of an object in a fluid to the sound speed in the same fluid in which that object moves.

For example, the sound speed in the air with a temperature of 25 degrees Celsius is 343 meters per second.

In general, the simulation of an airfoil requires the definition of a far-field boundary condition, and therefore the Mach number for the flow field must be defined, the value of which in the present case is 0.6.

Airfoil Conclusion

After simulation, we obtain two-dimensional contours of pressure, velocity, temperature, density, and Mach number, as well as two-dimensional streamlines.

The results show that at the leading edge of the airfoil, the highest pressure appears, caused by the airflow's direct contact with the airfoil's leading edge.

The structure of the airfoil is such that the airflow on its upper surface faces the greatest pressure drop. This pressure difference between the top and bottom of the airfoil body causes the upward movement of the wing.

Also, the velocity changes are in perfect accordance with the pressure distribution. Where there is the greatest pressure, the least velocity appears, and vice versa.