Aerodynamic and Aeroacoustics Predictions of Wells Turbines Using LBM

Oscillating Water Column (OWC) power plant is another form of “green energy” sources. It converts the motion of water waves into a bi-directional air flow which then drives an air turbine. The Wells Turbine, as a candidate for OWC power take off systems, was the object of considerable researches during the last decades. Optimization of aerodynamic performances reduction of noise generation is crucial for Wells Turbines to achieve great efficiency and meet acoustic regulations. The use of digital methods during the development process is then the way to avoid expensive prototypes and to optimize the OWC. In this paper, an unsteady and compressible computational approach based on the Lattice Boltzmann Method is used to simultaneously predict the 3-D turbulent flow and the corresponding acoustic field of a scaled model of the Wells Turbine. This scaled turbine was developed and intensively studied at Siegen University in Germany. The existing experimental aerodynamic and acoustic are first used to validate the numerical approach. In turn, the numerical results are used to investigate the origin of the noise as they provide insight on the link between flow structures and noise generation.