THEORETICAL AND EXPERIMENTAL EVALUATIONS OF STRAIN FIELD MODIFICATION INDUCED BY FLAWS IN LOADED COMPOSITE STRUCTURES (MODIFLAW)
The distribution of strains through a region of a body is referred to as a strain field. Damage or defects to loaded composite structures cause their strain field to be modified. The EU-funded MODIFLAW project therefore aims to develop, apply, and validate numerical models of strain field modification that is caused by the presence of flaws of different forms and sizes. It further aims to define virtual morphology for diagnostic indications provided by structural health monitoring (SHM) data and software on damaged subcomponents and structures. The project will advance research on novel inexpensive and low-weight processes and SHM technologies.
The project is led by VZLU based in Prague. The MODIFLAW is a European project of the joint technology initiative JTI Clean Sky 2.
MODIFLAW high level objectives are:
• To develop, apply and validate numerical models of the strain field modification induced by the presence of flaws with different kind of morphology and size.
• To define virtual morphology for diagnostic indications provided by the Structural Health Monitoring (SHM) data and software on damaged representative subcomponents and structures.
Technical development tasks include work packages:
- Modelling of the strain fields modification.
- Experimental determination of the strain fields on composite specimens and elements.
- Virtual morphology definition of diagnostic indication on subcomponents and representative component.
During the project Finite Element Method (FEM) model prototypes design of typical flaws, non-destructive inspection (NDI) and evaluation of specimens and elements, mechanical tests, impact damage tests, strain measurements using strain gages and DIC, and virtual testing using developed Structure Health Monitoring (SHM) software are performed.
The project results will contribute to innovative technologies which will be integrated into the Outer Wing Box on ground demonstrator and into the Fuselage structural demonstrator with the objective to obtain structural weight reduction, manufacturing and assembling recurring cost reduction, maintenance improvement and implementation of new eco-compatible materials and processes.
Vlach, J., Doubrava, R., Růžek, R., Horňas, J., Kadlec, M.: Linearization of Composite Material Damage Model Results and Its Impact on the Subsequent Stress–Strain Analysis, Polymers, 2022, 14(6), 1123.
Vlach, J., Doubrava, R., Růžek, R., Raška, J., Horňas, J., Kadlec, M.: Strain-Field Modifications in the Surroundings of Impact Damage of Carbon/Epoxy Laminate. Polymers, 2022, 14(16), 3243.
Raška, J, Vlach, J., Horňas, J.: Numerical evaluations of strain field modification induced by production flaws in loaded composite structures, MATEC Web Conf. 349 01013, 2021.
Vlach J., Raška, J., Horňas, J., Petrusová, L.: Impacted area description effect on strength of laminate determined by calculation, Procedia Structural Integrity, 35, 2022, Pp. 132-140, ISSN 2452-3216.
Kadlec, M., Vích, O., Novotný, D.: Composite Laminate Deflection during Low-velocity impact, EAN 2021 – 59th International Scientific Conference on Experimental Stress Analysis – Book of Full Papers, 2022, pp. 86–90.
VZLU – Czech Aerospace Research Centre (Czech Republic)
LEONARDO AIRCRAFT (I)
7/2020 – 09/2022
TECHNICAL RESPONSIBLE PERSON:
Martin Kadlec, PhD. firstname.lastname@example.org
LEAFLET: PROJECT OBJECTIVES AND CONCEPT
LEAFLET: PROJECT RESULTS