Active Turbulence Generation in a 3/4 Open-Jet Wind Tunnel

The focus of this thesis is on the replication of on-road turbulent flow conditions within a 1/10th scale model of a 3/4 open-jet closed-loop return wind tunnel. This type of wind tunnel is commonly used in the automotive industry for testing aerodynamic performance of vehicles. Often, these types of wind tunnels are used to produce a clean laminar flow and testing results are limited to these idealized conditions. A novel system is designed to produce a wide range of turbulence scales in the scale model automotive wind tunnel using activated grid elements. It is shown that the turbulence produced by the novel turbulence generation system can generate turbulent flows having Taylor Reynolds numbers between 70 and 890, and turbulence intensities between 3.3 % and 33.1 %, depending on proximity to the grid.