Multiscale surrogate modelling of the elastic response of thick composite structures with embedded defects and features

This paper presents a multiscale modelling approach for thick composite structures containing internal defects and features. The proposed approach was developed using a surrogate model to represent the composite response on the meso-scale. A set of Representative Volume Element (RVE) models under periodic boundary conditions were used to sample the response at specified locations across the composite design space. As an example of its application, wrinkle defects of various severities were introduced to the RVE models to assess the defect contribution to the composite response. The homogenized responses from the meso-scale RVE models were then used as input to the surrogate model. To link the macro and meso scales, a set of 3D lamination parameters representing the composite layup were developed. A surrogate model using the 3D lamination parameters and the defect severity as input was built to link the macro-model to the meso-scale responses. The proposed multi-scale approach was verified against a set of high fidelity models with different levels of wrinkle defect severity. Good agreement was found between the new multi-scale approach and the more computationally expensive high-fidelity models.