Contribution
Numerical Optimization of the Aeroacoustic Properties of Kite Lines in an Airborne Wind Energy System
* Presenting author
Abstract:
In the context of expanding renewable energy resources, airborne wind energy systems can make a significant contribution by harnessing the steady, high wind speeds at high altitudes. At higher wind speeds (Re = 4300), the kite lines in particular produce a tonal whistling noise. To suppress this flow-induced noise radiation, spiral surface structures are applied. These helical structures can reduce noise emissions by several decibels. The numerical optimization of these surface structures was performed using a hybrid, adaptive search algorithm, yielding designs promising a reduction of more than 10 decibels. The resulting sound pressure levels in the far field were calculated using the FWH model, relying on the results of a DDES simulation. Finally, the noise reduction and flow pattern predicted by the simulation were compared with the results from measurements conducted at various angles of attack. Utilizing both numerical methods and measurements, this study provides deeper insights into effective strategies for tonal noise suppression on cylindrical bodies using helical structures.