Transonic Flow over a 3D Airfoil: NACA 0012

Description

Transonic flow over an airfoil sits at the heart of compressible flow modeling, where local flow velocities approach and exceed the speed of sound, producing complex shock and expansion phenomena that govern aircraft aerodynamic performance. This CFD simulation uses ANSYS Fluent to model compressible airflow over a Naca 0012 airfoil in three dimensions, capturing transonic behavior at a Mach number of 0.7, an air temperature of 300 K, and a 2-degree angle of attack.

Methodology

A two-dimensional airfoil geometry is constructed with multiple zone divisions in ANSYS Design Modeler and extruded to form a three-dimensional computational domain. The domain is discretized in ANSYS Meshing using a structured grid of over 1.5 million cells. The simulation employs a pressure-based solver configured for compressible flow, using the Coupled pressure-velocity coupling algorithm, ideal-gas behavior for air density, and the Sutherland model to capture temperature-dependent viscosity. The setup runs as a steady-state simulation appropriate for transonic flow conditions.

Results Analysis

Post-processing examines velocity and pressure distributions around the airfoil to characterize the transonic flow field, including the effects of the 2-degree angle of attack on flow characteristics. The relationship between Mach number, local velocity, and pressure is analyzed to identify regions of compressibility effects and potential shock formation. These results provide insight into aerodynamic behavior in the transonic regime, relevant to aircraft design, aerospace research, and the broader study of compressible flow phenomena.