Modeling of offshore wind turbine noise radiation and propagation

Abstract

Noise generated by offshore wind turbine and support structure can radiate and propagate through the air, water, and sediment. Predicting noise levels around wind turbine structures at sea is required for the estimation of effects of the noise on marine life. To predict radiated noise, we used a finite element analysis (FEA) of a cylindrical shell model of a monopile structure. In the finite element modeling, transient modal dynamic analysis and steady state dynamic analysis (direct and modal) were implemented to simulate both construction and operational noise. The effect of various sediment types and foundation designs are investigated. The FEA package used was ABAQUS version 6.10. The output of the FEA analysis is used as starting field for acoustic propagation models such as PE to produce long range predictions. We present predictions of particle velocity at the structure-acoustic medium interface and sound pressure level as function of frequency at various distances from the structure. Laboratory experiments using scale models of the cylindrical shell have been carried out to verify the noise predictions. Comparison of the FEA model results and experimental data will be presented.