Digital Design strategies to certify and mAnufacture Robust cOmposite sTructures 

Project Information

DIDEAROT

Grant agreement ID: 101056682

DOI

10.3030/101056682

EC signature date 10 May 2022

Start date 1 September 2022

End date 31 October 2026

Funded under

• Climate, Energy and Mobility

Total cost

€ 4 702 366,25

EU contribution

€ 4 702 365,00

Coordinated by

CENTRE DE RECHERCHE EN AERONAUTIQUE ASBL - CENAERO
Belgium

Periodic Reporting for period 2 - DIDEAROT (Digital Design strategies to certify and mAnufacture Robust cOmposite sTructures )

Reporting period: 2024-03-01 to 2025-08-31

Summary of the context and overall objectives of the project

New certified designs for structures are critical for the upcoming changes in conception of aircraft architectures. Breakthroughs in design and new strategies for a better use of material and integration of functions in aircraft are required. Digital conception and simulation will play a role to reach a certified design that includes production scenarios before full manufacturing.

The level of complexity of phenomena being solved through dedicated modelling techniques is constantly evolving and faces many challenges in validation and exploitation. For better use of these methods, scalability, speed and representativity need to be addressed. In the DIDEAROT project, ongoing until 2026, the design process is addressed using appropriate Machine Learning surrogates, benefiting from High Performance Computing.

The roadmap of the DIDEAROT project is at the crossroads for a holistic robust optimization of composite structures focused on digital predictions of two key aspects in its lifetime:
1) Manufacturing: predicting distortions, stress build-up and assembly challenges for ever-more integrated industrial scale composite parts
2) Dynamic loads and impact: predicting damage and effects from loads occurring at high speed or repeated loads over time that can lead to critical certification conditions.

Micro- and meso-models are computed and build upon relying on digital technologies (data or simulation driven) instead of using each one of these one-off for material simulation, high-quality models will be developed through the scales to ensure optimized design approaches up to an industrial scale.
For mechanical behaviour of composites including damage, this means that accurate representation of the evolution of the material properties are achieved at the ply and structural level using hybrid models trained through a database of microscale RVE models run on a multitude of load cases.Manufacturing simulations use phenomenological curing models as building blocks. Hybrid models for the component level, capable of handling many design parameter evaluations will feed the full-scale simulations to reach robust design for manufacturing requirements. In parallel, improvements in the numerical schemes and high-performance computing of these multi-physical problems will finally validate the distortion and stress build-up in the structure.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Over the second reporting period of DIDEAROT, we advanced on the development of high fidelity simulations and efficient HPC exploitation as well as concentrated efforts on the implementation of machine learning approaches for vulnerability and manufacturing.
As all work packages have now started, leaders have taken on activities to specify the development framework:
- For work package 2 this includes the materials and the metrics of definition of the process induced distortion as well and the simulation of damage. The approach for digital twins is coordinated by Tecnalia and will concentrate on bringing life to the workflows built in the project
- For work package 3 geometries, configurations, and applications of interest for the manufacturing simulations are tested and validated as well as sensor technologies development. Work is carried out to intensify simulations & build machine learning approaches
- For work package 4, damage models at different scales are built through machine learning. This now covers non linear response in different conditions and must be tested and validated and made robust. Machine learning approaches are used to evaluate material evolution more rapidly in stochastic loading scenarios
- For work package 5, testing and comparison on larger scale demonstrators is under way. The approaches to build robust validation through certification and intensify use of HPC on structural multi-physical applications is studied.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

In results for process simulation for manufacturing, progress past the state of the art include analysis of different numerical approaches to solve the problem of curing process for a composite part inside an autoclave. These numerical approaches will be classified in two distinctive groups based on transversal methodologies (AI & Machine learning and HPC). The first group will include hybrid-methods based on ML algorithms trained with synthetic/experimental datasets. While the second group will be focused on advanced simulations (direct FEMs) capable to perform a fully coupled fluido-thermo-structural simulation by making use of multiphysics HPC codes.

Simultaneously, two main progresses beyond SoTA are targeted for damage modelling:
• First, set-up accurate physics-based models capturing all damage mechanisms at micro and meso scales so to have a reliable source of synthetic data.
• Then, develop material specific AI/ML methodologies, to be used in conjunction with the hybrid methods of Trans 1 theme, allowing to speed-up multi-scale modelling by 5 order of magnitude while keeping sufficient accuracy.

For AI & Machine Learning, the consortium is analysing strategies to reduce the complexity of the classical approximations for solving parametric (differential) physical equations by means of FEMs.
Conjugation of reduced order models (ROM not only limited to classical linear methods but including non-linear ones based on machine inference) with FEM models, study of temporal relationships in simpler vector spaces, down-sampling techniques or metamodels are being used.

On the front of HPC, DIDEAROT progresses beyond the state of the art exploring different numerical methodologies for the design cycle of aircraft structures taking benefit of existing frameworks based on HPC.

Last but not least, the use of HPC will not only be applied to solve large-scale problems, but also to generate the synthetic dataset for training the machine learning models (hybrid methods) for both process & damage modelling. These approaches will contribute to the generation of data for further advanced models based on machine learning.

Approaches for simulation of damage in materials at different scales using hybrid techniques

Improved digital testing pyramid for certification of composite materials

Example of interaction of mechanical models for composites at different scales