Researchers analyzed real-world measurements from Swedish wind farms (e.g., Målarberget with Vestas V150 turbines and Lervik with SG170 turbines) and validated them with advanced 3D simulations (SoundSim360 tool).

Modern large turbines (tall hubs ~200m, large rotors) produce stronger infrasound signals (below 20 Hz, inaudible) than older, smaller models.

Levels are significantly higher than previously reported/assumed in many models.

Infrasound propagates farther than earlier assumptions, influenced by terrain, weather, wind direction, and atmospheric conditions (e.g., stable nighttime layers enhance propagation).

Shutdown tests at sites like Målarberget confirmed the turbines as the source: signals dropped markedly when turbines stopped, showing periodic pressure pulses tied to blade-tower interactions.

The study highlights limitations in standard calculation models (e.g., they may underestimate real propagation under certain conditions).

There is a recent Swedish research (primarily 2025–2026) on infrasound from modern wind turbines, led by Professor Ken Mattsson at Uppsala University.

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Efficient finite difference modeling of infrasound propagation in realistic 3D domains: Validation with wind turbine measurements

This is the full title of the peer-reviewed paper by Ken Mattsson and colleagues (Gustav Eriksson, Leif Persson, José Chilo, Kourosh Tatar), published in Applied Acoustics Volume 243, February 2026 (Article 111156).

It became available online around November 2025 and is open access.

Abstract (Full)

We present a high-fidelity simulation tool for accurate acoustic modeling across a wide range of applications.

The numerical method is based on diagonal-norm Summation-By-Parts (SBP) finite-difference operators, which guarantee linear stability on piecewise curvilinear multi-block grids.

Realistic three-dimensional atmospheric and topographic data are directly incorporated into the simulations, and the solver is implemented in CUDA to achieve high computational efficiency.

Verification is performed through convergence studies against highly resolved benchmark problems in both two and three spatial dimensions, while validation is carried out using high-quality infrasound measurements from two modern wind farms in Sweden.

The results show that modern, large-scale wind turbines generate infrasound levels significantly higher than those reported for older, smaller turbines.

These findings advance the understanding of the acoustic characteristics of contemporary wind turbines and provide important guidance for assessing their potential environmental and societal impacts.

Highlights

• 3D low-frequency simulation tool for complex domains.
• Validation against infrasound wind farm measurements.
• Verification against realistic 2D and 3D benchmark problems.
• Verification of long-propagation effects in different atmospheres.
• Determination of the infrasound sound power levels of modern wind-turbines.

Key Technical Aspects

The paper introduces and validates SoundSim360, a physics-based tool solving the 3D acoustic wave equation using high-order SBP-SAT finite difference methods. It handles complex terrain, realistic atmospheric profiles (including wind, temperature gradients/stratification), and propagates sound efficiently on GPUs (CUDA).

Validation used field measurements from Swedish sites like Målarberget (Vestas V150 turbines) and Lervik (SG170 turbines). Shutdown tests helped isolate turbine contributions. The model matches measured infrasound pressure pulses (tied to blade-tower passage) and shows better performance than traditional models (e.g., ray-tracing like Nord2000, which underperforms at low frequencies due to poor diffraction handling).

Main Result: Modern large turbines (tall hubs, big rotors) produce higher infrasound sound power levels than older/smaller ones. Propagation is stronger/longer-range under certain conditions (e.g., stable nighttime atmospheres) than many prior assumptions or simplified models indicated.

The introduction discusses broader context: low-frequency noise concerns, limitations of common models, infrasound from various sources, and notes personal symptoms experienced by researchers during high-exposure measurements (e.g., ~95 dB around 1 Hz), referencing related health literature—though the core paper focuses on acoustics/modeling, not a dedicated health study.

Access

ScienceDirect: https://www.sciencedirect.com/science/article/pii/S0003682X25006280 (open access).

PDF mirrors are available via sites like Wind Watch (search the title).

This work strengthens calls for updated noise assessment methods, site-specific modeling (especially nighttime), and better accounting for infrasound in permitting. It builds on the team’s measurement campaigns and prior tool development.

Published: Applied Acoustics Volume 243, February 2026 (Article 111156)

DOI: 10.1016/j.apacoust.2025.111156

Authors: Ken Mattsso, Gustav Eriksson, Leif Persson, José Chilo, Kourosh Tatar