Lamb wave modes repulsion in multi-layered structures

• Applicants: Professor Dr.-Ing. Bernd Henning; Dr. Jens Prager
• Subject Area: Mechanics ; Measurement Systems
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 449607253

In the LaWaMoRe project, the aim is to develop a non-destructive testing method for the characterisation of coupling strength between two layers using mode repulsion regions appearing in the dispersion curves of multi-layered structures. To the authors’ knowledge, the current project is the first attempt to understand and characterise the mode repulsion with respect to the coupling strength. The hypothesis is that coupling strength between two layers can be characterised through measuring the distance, in terms of frequency or phase velocity (wavenumber), between two coupled modes in a mode repulsion region. Within the LaWaMoRe project correlation between mode repulsion and the coupling strength will be explored and quantified. To reach the aim of the project, both numerical and experimental investigations will be carried out. BAM has a lot of experience in numerical modelling, especially the Scaled Boundary Finite Element Method to be used in the project and will provide necessary destructive testing for the validation of the non-destructive method to be developed in the project. EMT has years of experience in the development of the measurement methods, especially for the characterisation of material properties and employment of the inverse procedures which are other key aspects of the project. The combination of the competences and experiences of both institutions in the LaWaMoRe project will make an important contribution not only to the scientific community but also to the industry allowing for the non-destructive characterisation of the quality of adhesive joints.

• DFG Programme: Research Grants