Author:

Keywords:

Science & Technology, Technology, Engineering, Mechanical, Mechanics, Engineering

Abstract:

This paper investigates the structure-borne and airborne noise radiated from a wind turbine gearbox. A flexible multibody model is used to calculate the structural deformations of the gearbox during a 120 sec RPM runup going from zero to nominal RPM. An acoustic FE model is set up to compute the acoustic response during this RPM runup, based on the structural deformations. Emphasis has been put on the accuracy of both multibody and acoustic models. For the multibody model, it is shown that flexibility of the major gearbox components is required to obtain reliable results. On the gearbox housing, which is the largest flexible component of the gearbox, a mesh convergence study is performed and the influences of 6 large bolted connections on the modal behaviour of the gearbox housing are investigated. The need for an advanced acoustic model is shown by calculating the radiation efficiency of the gearbox housing. It also shows how an acoustic model can be efficiently combined with a flexible multibody model allowing to calculate the acoustic response from a time simulation. Using these models, an initial acoustic simulation is performed and presented.