Dynamic characteristics analysis of cracked wind turbine blade

Wind turbine is a clean, renewable and sustainable energy technology that makes it extremely important to promote global energy transformation and achieve low-carbon development. Cracks in wind turbine blades reduce their stability and lifespan and may lead to significant safety hazards. Therefore, a blade for the 5MW wind turbine was modeled with the method of layering by zones and sections, and the dynamic characteristics of cracks at different positions of the wind turbine blade are analyzed. It can be found that the maximum stress is the highest when a crack is located at the root of the blade, and the maximum stress from the crack will gradually decrease from the blade root to the blade tip. At the same time, the cracks at the blade root will propagate towards the blade middle over time. Combined with digital speckle technique and wind tunnel, an experimental platform for dynamic characteristics of wind turbine blades was constructed. The dynamic characteristics and crack propagation trend of cracked blades were analyzed, and the experimental results were compared with the theoretical analysis. It is found that the experimental results are in agreement with the theoretical analysis conclusions.