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Despite the fact that there is an existing body of literature addressing the computation of Coupling Loss Factors (CLFs) via the Finite Element Method (FEM), no publications have sufficiently taken into account real structural joints in their approach. Previous research has focused on academic cases of trivial connections, rarely involving more than two steel plates. To enable Statistical Energy Analysis (SEA) on a real ship, a methodology for determining CLFs for non-trivial systems is proposed, considering realistic boundary conditions and irregularities that can occur in marine structures. Based on the method, a library of CLFs is created by selecting the tested connections to enable modelling of about 90% of the acoustic paths on an existing jack-up vessel. Boundary conditions were set by introducing spring elements with a stiffness calibrated to the type of connection and taking the adjacent structure into account. In previous works, CLFs were determined for basic connections of rectangular plates. The lack of scantling variations, ignoring discontinuities and only defining parallel edges in the considered models, lead to the overestimation of energy transmission in real structures. To consider the influence of the above, random deviations from the initial stiffness of the springs at individual edges and point restraints at random points are introduced in this paper.

Results of model tests of a rotating composite beam with integrated piezoelectric active element are presented in the paper. A proposed electromechanical system is a simplified model of the structure of a modern helicopter rotor blade. Numerical analysis of the considered system is developed by means of the finite element method. In addition, the laboratory setup has been built in order to perform real experimental studies. Selected static and dynamic characteristics of the object are determined by a series of numerical simulations. The results are compared with the outcomes of tests performed on the experimental setup. A very good agreement between numerical simulation and experiment results is observed. [ABSTRACT FROM AUTHOR]

The study concerns a flat large construction steel plate of varying thickness magnetized with a C-core magnet. Modeling of the time- and space-field distribution inside the plate is carried out. The novelty of the approach consists in carrying out a transient solution when a driving saw-tooth voltage is used. Also new is a refined magnetoacoustic emission (MAE) signal modeling, numerically deduced for various frequencies, and compared with experimental data. The distributions of fields are indirectly compared with stray field measurements and a close agreement is found. [ABSTRACT FROM AUTHOR]

Abstract: The study concerns ferritic steel tubes of varying thickness magnetised with a C-core magnet. Modelling of the internal time- and space-field distribution is carried out. A finite element (FE) time-transient solution is applied, taking into account the material nonlinear B(H) characteristics, eddy currents and a saw-tooth form of the driving voltage. [Copyright &y& Elsevier]