A stochastic material model to describe continuous mode conversion

Deterministic material models are not able to comprehensively describe phenomena observed in experiments. The continuous mode conversion (CMC) of propagating waves in carbon fiber reinforced plastic (CFRP) plates is an example of this. The mechanism is similar to the conversion in the presence of defects. If a symmetrical mode while propagating through a plate‐like structure encounters a damage, which is non‐symmetric with respect to the waveguide thickness, the symmetrical mode converts into an asymmetric mode at the obstacle. The conversion is usually bounded to the location of the obstacle. In contrast, the CMC occurs even in damage free CFRP structures and manifests itself in conversion taking place permanently or continuously. The reason for this phenomenon is the irregular distribution of fiber and matrix material. With the extension to the stochastic context, it is possible to work out an enhanced material model which is able to reproduce the observed wave behaviour.