Understanding atmospheric motion is crucial for analyzing wind-structure interactions, particularly within the Atmospheric Boundary Layer (ABL). Traditionally, wind tunnels have simulated unsteady ABL conditions using active and passive devices. Recently, multi-fan wind generator
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Understanding atmospheric motion is crucial for analyzing wind-structure interactions, particularly within the Atmospheric Boundary Layer (ABL). Traditionally, wind tunnels have simulated unsteady ABL conditions using active and passive devices. Recently, multi-fan wind generators have emerged as a flexible, cost-effective alternative, allowing independent fan control to replicate wind conditions the wind turbines, airborne devices or civil structures are subjected to.
This thesis investigates the capability of a newly manufactured 3 x 3 multi-fan wind generator to produce idealized uniform flow, linear shear flow profiles, and streamwise sinusoidal gusts. The system consists of off-the-shelf computer fans, controlled via open-source software, offering a low-cost and adaptable approach. Particle Image Velocimetry (PIV) measurements show a 96% uniform core region with 11.5% turbulence intensity 1 m downstream from the system. There, the area of the core is reduced to 1/9 of the system’s area due to the outer shear layer. The system struggles to replicate linear wind shear, but can generate oscillatory gusts at 0.2 Hz, 0.4 Hz and 0.8 Hz, corresponding to the operating frequency of the fans. Further improvements should focus on extending the configuration to maintain a larger core region, and on reducing swirl dynamics and recirculation to enhance flow quality for wind engineering applications.