In this paper, according to different locations of blade fracture accidents, it is divided into three fractures: blade root fracture, leaf middle fracture and blade tip fracture. Assuming that the blade fracture accident due to aging is operated at the rated wind speed and rated speed, CFD simulation is carried out to analyze the wind rotation field, aerodynamic load and blade surface streamline characteristics of NREL 5MW wind turbine with different fracture positions. This paper also assumes that under the condition of a strong typhoon, the instantaneous wind speed is too large, resulting in the wind turbine speeding, and then the blade fracture accident occurs. At this time, the wind turbine was running under extreme wind speeds, and the speed soared due to the speeding car. Analyze aerodynamic loads at different speeds. It provides an important reference for the design and operation and maintenance of wind turbine blades.

Guo Li. CFD simulation analysis of aerodynamic characteristics of large wind turbine unit under accident condition. International Journal of Frontiers in Engineering Technology (2023), Vol. 5, Issue 3: 16-25. https://doi.org/10.25236/IJFET.2023.050304.

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