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Generic Linking of Finite Element based Models

Tags: Air

State of the Art - Background

Engineers need to conduct large-scale computational analysis of, for example, entire aircraft structures. One issue that arises during the modelling of such structures is the need to conduct a unified analysis of an assembly of individual structural models that are coupled and were developed independently. Typically, these individual models were created by different engineers at different geographical locations using different software, or they can be present due to local analysis of complex physical behaviour.

As a result these individual models are likely to be incompatible with interfaces. Therefore, it is very difficult to combine them for a unified analysis of the entire assembly. Global-Local Finite Element (FE) methods enable the joining of independently modelled substructures. In addition, these methods allow for a hierarchy of mesh refinements on components and the use of complex finite elements within generic finite element meshes.


The strategic project objectives are to reduce aircraft development costs, reduce lead times, and establish a more competitive supply chain. This can be achieved by enabling companies within the aeronautical supply chain to seamlessly couple their analysis capabilities by solving analysis model interfacing. This advanced interfacing will enable companies in the supply chain to cooperate in new profitable ways providing a combination of adaptive accuracy, ease of use and tailored intellectual property protection.

The operational project goal is to derive innovative methods to couple finite element-based structural analysis models of different origin and modelling fidelity. Applying the coupling methods has to be generic, i.e. it comprises different local phenomena (e.g. multi-scale progressive damage), analysis capabilities (e.g. strength, stability), scales (entire aircraft versus detailed components), materials (composites, metals), and demands on accuracy and efficiency. Additionally, the coupling procedure is to be automatic, i.e. local models are automatically created and analysed where necessary, and the local-global coupling is automatically integrated within the (iterative) global FE analysis.

Subsequent to the development, the coupling approaches considered in this study will be applied to several use cases that are considered representative for industry. The goal is to find the best approach among the ones considered and to verify utilization by porting the best approach to a commercial driven code. The goals of this research are summarized in the Figure below.

Description of Work

The work plan is divided into one management and six technical work packages (WP).

WP0 is comprised of all activities related to the project and WPs coordination.

WP1 specifies the detailed functionalities that are required to meet the project objectives. In addition, the level of required accuracy and the metrics to assess project performance will be established.

WP2 explores the theory on coupling approaches, assesses and improves the theory to meet the project objectives.

WP3 implements coupling approaches within existing software environments. The code language will depend on project requirements stated in WP1. The class implementation will be 'generic', so that it will be easy to integrate with existing software code.

WP4 conducts benchmarks of software implementation. In addition, mathematical algorithms that are used within the research are validated.

WP5 benchmarks newly developed code via pre-determined test cases. In addition, these benchmarks show that the industrial need is properly addressed. The code is validated by comparing commercial driven code and research driven code.

WP6 is concerned with writing and publishing a book. This book will cover all the theory and results related to the coupling approaches studied for this project.

Expected Results

The research conducted in this study will provide companies within the aeronautical supply chain with advanced methods and computational tools to seamlessly couple their analysis capabilities via accurate analysis model interfacing. More specifically, the deliverables provide automatic coupling of finite element based structural analysis models of different origin and modeling fidelity where no interaction during initial model creation is present.

The developed theory will be implemented into commercial finite element code. In addition, benchmark problems are defined and means to execute and verify the developed approaches will be documented. Via publications at conferences and in scientific journals the developed theory and results will be made publicly available. In addition, a book will be published covering the research conducted and the results obtained during this study.

In the context of virtual testing, glFEM will expand the multi-scale coupling capabilities. Interaction of different models on different length scales will be clearly defined enabling an automatic coupling between local and global FE analyses. This automatic coupling includes iterative processes, forward/backward interactions as well as automatic generation of local models. The local models involve local effects that influence the global structural behavior (e.g. skin-stringer de-bonding or local material damage).

In summary, the novel contribution of glFEM is an explicit investigation and establishment of innovative and reliable coupling approaches, which are automatic, iterative, generically applicable and not limited to a one-shot or one-way solution.

Focus areas of the glFEM project.
Focus areas of the glFEM project.