Posters
Come meet the poster presenters to ask them questions and discuss their work
We would like to invite you to come and see the posters at our upcoming conference. The posters will showcase a diverse range of research topics, and will give delegates an opportunity to engage with the authors and learn more about their work. Whether you are a seasoned researcher or simply curious about the latest developments in your field, we believe that the posters will offer something of interest to everyone. So please join us at the conference and take advantage of this opportunity to learn and engage with your peers in industry and the academic community.
PO358: Accounting for wind turbine noise horizontal directivity: acoustic and financial impacts
Arthur Finez, Acoustic Engineer, ENGIE
Abstract
Wind turbines are usually considered omnidirectional sources for acoustic impact studies of wind farm projects, despite several studies demonstrating their complex acoustic directivity. This assumption leads to inaccuracies in estimates of sound levels around wind farms, possibly inducing over curtailment. This study aimed to integrate acoustic directivity into the calculation of curtailment plans. A parametric model of horizontal directivity was therefore developed based on experimental data from a dedicated measurement campaign, including various yaw offsets. The model extends Okada’s formulation to capture the complex lobes and asymmetries revealed in the experimental data. It was validated for frequencies up to 1000 Hz and wind speeds from 6 to 14 m/s, with a further validation of the overall sound pressure level at dwellings. The model was then integrated into sound propagation calculations and used to assess the errors in estimates of sound levels induced by the omnidirectional assumption. This raised concerns about the choice of estimating the sound power level Lw from a single downwind measurement. Moreover, curtailment plans obtained with and without accounting for directivity were compared across six wind farms, focusing on the financial and acoustic impact of integrating directivity. This work illustrates how directivity enables refined curtailment plans, through a detailed case study of one wind farm. The results showed consistent reductions in production losses, with an average of 1,1% of net annual energy production. Furthermore, the acoustic impact of taking directivity into account remains moderate, since sound level increases exceeding 1 dB at dwellings occurred less than 3% of the time across all studied wind farms. Finally, the omnidirectional model was found to slightly overestimate sound levels most of the time. This work highlights the relevance of considering acoustic directivity and the need for increased turbine flexibility to enable more refined and efficient curtailment strategies.
No recording available for this poster.
