Wind Tunnel: Compressible Flow

Description

This project models a wind tunnel and a specific body placed inside it using ANSYS Fluent, with the goal of investigating the drag force acting on the body. The wind tunnel is one of the most widely used aerodynamic testing tools in use today, enabling experiments on structures such as airfoils, aircraft, and static bodies to study aerodynamic behavior and visualize flow patterns. Wind tunnels can also be used for free-fall tests, examining how airflow affects a falling object, and since forces such as drag significantly influence a body's behavior, quantifying them accurately is essential — a task CFD is well suited to.

Methodology

The geometry is created in ANSYS Design Modeler and meshed in ANSYS Meshing using an unstructured grid totaling 179,542 elements. A density-based (compressible flow) solver is used in this simulation, with the energy equation activated to capture the compressible-flow physics across a range of inlet Mach numbers.

Analysis

The solution produces contours of velocity, pressure, temperature, and related quantities across the studied Mach numbers. The velocity vectors reveal the formation of separation vortices behind the body, and as a result of this separation, flow turbulence in the wake is substantial — noticeably greater than in the rest of the computational domain, illustrating how body geometry drives the wake dynamics that underlie drag generation.