3 results about "Extended finite element method" patented technology

The present application belongs to the technical field of wind power generation, and specifically relates to a wind power tower material crack propagation prediction method and system, which is suitable for fatigue life evaluation of large supporting structures in the wind energy industry. The method comprises: deploying a multi-source heterogeneous sensor network to collect strain, acoustic emission and environmental load data; constructing a digital twin high-fidelity finite element submodel to obtain a dynamic stress intensity factor; constructing a deep neural network, embedding the Paris law of fracture mechanics in the form of residual into the loss function to form a physical information neural network, and realizing crack propagation rate prediction; using the extended finite element method combined with the level set function and the maximum circumferential stress criterion to dynamically track the three-dimensional space expansion path of the crack; combining Monte Carlo simulation and recursive Bayesian update to evaluate the remaining life and trigger graded early warning. The present application solves the problems of insufficient fusion of physical mechanisms and data-driven in the prior art, low prediction accuracy under small samples, and lack of crack space path tracking.

The invention discloses a pressure pipeline inner surface crack risk assessment method based on extended finite elements and stress triaxality, and aims to solve the problems that an existing method is insufficient in precision and ignores a coupling effect, and comparison files are limited to extreme working conditions. The method comprises the following steps: establishing and verifying an XFEM basic model, constructing a pipeline XFEM model containing inner surface cracks, revealing a crack size-angle coupling rule and identifying a critical angle of 8-12 degrees, predicting crack propagation based on stress triaxial degree, and carrying out risk grading and detection priority ranking in combination with the coupling rule. According to the method, the size-angle coupling effect is innovatively quantified, the stress three-axis degree is upgraded into an independent extension prediction tool, a complete engineering closed loop is formed, the evaluation error is smaller than or equal to 10%, the method is suitable for conventional operation and maintenance of 09MnNiDR low-temperature steel pipelines and the like, an RBI plan can be directly optimized, and the practicability and the universality are remarkably superior to those of a simulation technology optimization guiding scheme of a comparison file.