Non-intrusive two-scale coupling strategy of non-compatible models for the tolerance analysis of composite structures to local features
Résumé
Imperfection tolerance analysis in composite structures requires suitable computational strategies which can be easily integrated into the finite element codes commonly used in engineering. A surface coupling method of homogeneous and heterogeneous continuous models is proposed in order to transmit a state of macroscopic strain on the local zone of interest consistent with the behavior of the global model. The developed coupling technique is based on a second-gradient kinematics but does not require the explicit construction of the homogenized operator.
In response to the industrial needs, a non-intrusive coupling fixed-point algorithm is used to efficiently solve the coupled problem. It iteratively substitutes the behavior of the local “fine” model in that of the “coarse” model of the healthy structure and only uses features and data easily accessible via an API in common FE codes. Also, an implementation of the coupling conditions using Multi-Point Constraints is presented. Implemented in Z-setTM(ZeBuLoN) for the local-global analysis of a laminated woven composite presenting a localized anomaly due to the weaving process, the non-intrusive computational strategy leads to results in the zone of interest of much better quality compared to classical submodeling technique and for a relatively low development cost.