ElMaR research project

Project title: ElMaR – Non-destructive determination of local material parameters in rotor blade components

Summary:

In the design of rotor blades, fiber composite materials are regarded as ideally smeared, homogeneous materials. The required material parameters are determined in material tests at coupon level. It is known that the material properties of fiber composites are subject to fluctuations. The uncertainties of the material parameters are taken into account in the blade design by means of partial safety factors. Spatial variation of the material parameters and their possible consequences are not taken into account. However, a closer look reveals that the assumption of a homogeneous material is already incorrect at coupon level. It is to be expected that the spatial variation of material parameters at the structural level of a rotor blade will be significantly higher due to the manual work steps. This also increases inaccuracies in the prediction of fatigue life and load-bearing capacity, which leads to an unnecessary reduction in structural reliability. In order to develop probabilistic models, specify partial safety factors and thus increase the structural reliability of rotor blades, the project pursues the following specific objectives: – A method for the non-destructive determination of spatially fluctuating material parameters in rotor blade components is to be developed. The research hypothesis is that a combination of established imaging methods, modern machine learning algorithms and high-resolution simulation methods is suitable for combining very high accuracy with short computing times. – The method is to be validated in the laboratory at the structural level. – After completion of the project, a consortium with industrial participation is to be organized in order to connect a funded joint research project with the aim of further developing the method towards industrial applicability.