This presentation was made at CAASE18, The Conference on Advancing Analysis & Simulation in Engineering. CAASE18 brought together the leading visionaries, developers, and practitioners of CAE-related technologies in an open forum, to share experiences, discuss relevant trends, discover common themes, and explore future issues.

Resource Abstract

Crack propagation life assessment of engineering structures is an integral part of well-established Damage Tolerant Design (DTD) practices in aeronautical industry. In the recent years other industries adopted DTD procedures to design components that pose safety concerns. New developments (Structural Health Monitoring, Probabilistic Rotor Design) that make use of fatigue and fracture knowledge emerged in an effort to better quantify inspection intervals, set maintenance procedures or assess the risk of failure. The Digital Twin concept laid out by AFRL and NASA, re-emphasizes development of three-dimensional deterministic damage accumulation models reinforced by probabilistic methods to assess structural integrity of an aircraft structure. The need for robust and ease-of-use damage modeling capabilities at component level is desirable for a more accurate predictive life assessment capability in the industry.
Various finite element modeling capabilities have been developed at Simmetrix to satisfy the industry level requirements for crack propagation simulation and life assessment. The procedures employ existing CAD models or component level finite element meshes to efficiently reuse data developed in the design process. The crack insertion process can use a planar or non-planar surface definition to represent the initial crack surface and further simulate crack propagation in any geometry without constraining crack surface to a predefined shape. Same procedure is followed to define, insert and mesh models containing multiple cracks without additional effort from the user to pursue a more complex life assessment. For composite structures, the developed capabilities allow single or multiple crack insertion along a three-dimensional material interface or across the interface to support delamination studies or translaminar damage life assessments. Another area where these lifing related modeling capabilities could be applied, are related to segmentation and reconstruction of volumetric measurements. Different examples are presented to provide details on implementation and portability of the remeshing procedures to demonstrate usability of damage modeling capabilities.