A Hybrid Aerodynamic and Aeroacoustic Modeling for Small Wind Turbines

Abstract

The present paper is concerned with a hybrid method to calculate the sound field generated by the blades of wind turbines. There is given the background of the current state of the art, from which it becomes clear that the problem in hand is nowadays under thorough investigation, due to its significance for engineering applications. Then an alternative treatment of some classical fundamental basics is undertaken. The key point is that the aerodynamic and aeroacoustic fields are calculated separately. The first one is calculated by a standard FEM package, on the basis of non-stationary Navier-Stockes equations for viscous incompressible fluid. Then the classical Lighthill-Curle aeroacoustic theory is used, whose particular treatment allows one to construct the acoustic wave field generated by the rotating blade. Finally, in order to test the precision of the direct numerical technique, the numerical solution is compared with experimental results obtained on a small single-blade wind-turbine.