Efficient semi-analytical simulation of elastic guided waves in cylinders subject to arbitrary non-symmetric loads

Notes on osculations and mode tracing in semi-analytical waveguide modeling

“…In addition, we wish to restrict the discussion to Hermitian eigenvalue problems. There are several closely related methods to achieve this goal, in particular, the thin layer method (TLM) [21][22][23], scaled boundary finite element method (SBFEM) [24][25][26] and semi-analytical finite element method (SAFE) [27][28][29]. For the simple application discussed here where only systems of a constant cross-section in the frequency domain are addressed, these methods can be considered to be equivalent.…”

P59 - Improved Determination of Viscoelastic Material Parameters Using a Pulse-Echo Measurement Setup

“…Otherwise, the received signals would be too small to evaluate, especially when investigating polymers with greater attenuation. By knowing both, the input and output, material parameters of a sample can be determined in an inverse approach by modelling the sample as a hollow cylindrical waveguide via an SBFE method [1,2]. Previous studies of the measurement setup show a low sensitivity of the mechanical shear parameter µ L due to the uniform full surface excitation of the transducers [1].…”

On the forward simulation and cost functions for the ultrasonic material characterization of polymers

“…1 Such simulations are usually computationally demanding, however, the use of the scaled boundary finite element method reduces this overhead [1]. A model on the basis of cylindric domains with non-symmetric boundary conditions has been implemented to obtain an efficient model as the foundation of the optimization procedure [2]. In this paper, the model setup is based on a ring configuration with two phase-shifted excitations [3].…”