The path to virtual testing for certification of large composite wind turbine blades: Challenges, progress and insights

Rapid innovation in wind turbine blade design has resulted in blades that exceed 150 metres in length, this progress has also intensified the challenges associated with traditional blade certification. Full-scale physical testing has become increasingly expensive, time-consuming, and ultimately a barrier to rapid innovation and market entry. These limitations motivate a shift towards virtual testing frameworks capable of delivering reliable, certifiable evidence of structural integrity and reliability of large composite blades. This issue motivates a transition towards virtual testing methods that can provide dependable, certifiable insights. Current certification procedures are reviewed, and the technology readiness to replace physical testing with virtual testing is assessed for both current and emerging technologies. The review finds that several methods are sufficiently mature to support pre-static and static test validations. However, virtual fatigue testing remains a major bottleneck due to the computational resources needed to virtually test such complex fatigue problems with sufficient accuracy and consistency to replace the physical tests. To address these constraints, this work also analysed recent advances in multiscale modelling, probabilistic and data-driven methodologies, and physics-informed neural networks. Although these techniques show strong potential on smaller-scale demonstrations, key challenges — including limited high-quality data, insufficient computational infrastructure, and concerns about model transparency — continue to impede their adoption in full-scale certification. Significant research and development are still required before virtual fatigue testing can replace conventional physical tests.