In the quest to harness the power of the sea, offshore wind farms are becoming a cornerstone of global energy strategies. However, the very forces that make these installations powerful also pose significant challenges, particularly the scouring effects of waves on the foundations of wind turbines. A recent study published in the journal *Water Science and Engineering* sheds new light on this critical issue, offering insights that could shape the future of offshore wind energy.
The research, led by En-yu Gong from the College of Water Resources and Civil Engineering at China Agricultural University, addresses a longstanding problem in the field: the reliability of small-scale physical models when extrapolated to full-scale offshore environments. “Traditional small-scale experiments often fall short in accurately predicting scour patterns and depths in real-world conditions,” Gong explains. “Our study aimed to bridge this gap by conducting large-scale experiments that more closely mimic field conditions.”
The team conducted experiments at a scale of 1:13, focusing on both slender and large monopiles—the foundational structures that support offshore wind turbines. They subjected these structures to irregular waves, which are more representative of real-world conditions than the regular waves typically used in laboratory studies. The experiments covered a range of Keulegan–Carpenter numbers (NKC), a dimensionless parameter that characterizes the wave-induced flow around a cylindrical structure, and diffraction parameters (D/L), which relate the diameter of the monopile to the wavelength of the waves.
For slender monopiles, the study found that the maximum scour location and the shape of the scour hole were strongly influenced by the NKC value. Interestingly, the patterns observed under irregular waves differed from those under regular waves, highlighting the importance of using more realistic wave conditions in experimental designs. “Improving the calculation of NKC under irregular waves enhanced the accuracy of existing scour formulae,” Gong notes, suggesting that refined models could lead to more precise predictions and better-designed foundations.
For large monopiles, the maximum scour locations were consistently found on both sides of the structure, regardless of the NKC and D/L values. However, the topography of the scour hole was influenced by both parameters. Notably, the scour range around a large monopile was at least as large as the monopile diameter, a finding that could have significant implications for the design and maintenance of offshore wind turbine foundations.
The study’s findings are particularly relevant for the energy sector, where the reliability and longevity of offshore wind farms are paramount. “Understanding scour patterns and depths is crucial for designing foundations that can withstand the harsh marine environment,” Gong says. “Our research provides valuable data that can inform better engineering practices and reduce the risk of structural failure.”
As offshore wind energy continues to grow, the insights from this study could shape future developments in the field. By improving the accuracy of scour predictions, engineers can design more robust and cost-effective foundations, ultimately enhancing the viability and sustainability of offshore wind power. “This research is a step towards more reliable and efficient offshore wind energy solutions,” Gong concludes, underscoring the potential impact of the findings on the energy sector.
Published in the journal *Water Science and Engineering*, this study offers a compelling example of how large-scale experiments can bridge the gap between laboratory research and real-world applications, paving the way for more resilient and efficient offshore wind energy systems.