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Abstract: In this paper the Network Simulation Method (NSM) is proposed as a tool for solving the transverse-motion of thin beams resulting from a bending action. The reliability and robustness of the proposed technique is demonstrated with two examples, in which a pinned–pinned beam and a clamped-mass load beam are, respectively, submitted to different flexural forces. The NSM is a numerical technique for the solution of linear and non-linear problems, which are defined by a mathematical model. Assuming that the electrical variables of voltage and current are equivalent, respectively, to the displacement and the spatial variation of the displacement, a network model for each volume element is designed such that electrical equations are formally equivalent to the spatial discretised equations of the mechanical model. The whole network model, including the devices associated with the boundary conditions, is solved by the numerical computer code PSPICE. The numerical results have been compared with those obtained by the mode-superposition method: the agreement between them is impressive. The temporal behaviour of each quantity involved in the problem is obtained without transform complications, since the whole study has been conducted in the time-domain, with the possibility of obtaining the corresponding spectral content at the end of calculation. The main contribution of the present paper, therefore, is to employ the NSM numerical method in order to arrive at solutions, in the time-domain, of dynamic mechanical problems. One must also emphasize that NSM has not previously been used by other authors to solve physical problems like the ones presented here. [Copyright &y& Elsevier]

Abstract: This paper concerns a two dimensional numerical model based on a high-order boundary element method with fully nonlinear free surface boundary conditions. Multiple fluxes are applied as a method of removing the so-called “corner problem”, whereby the direction of the outward normal at geometric discontinuities is ill-defined. In the present method, both fluxes associated with differing directions of the outward normal at a corner are considered, allowing a single node to be placed at that position. This prevents any loss of information at what can be an important part of the boundary, especially if considering simulations of wave reflection and wave run-up. The method is compared to both the double node approach and the use of discontinuous elements and is shown to be a more accurate technique. The success of the method is further demonstrated by its ability to accurately simulate various problems involving wave transmission and wave-structure interactions at domain corners; the results being achieved without the need for filtering, smoothing or re-gridding of any kind. [Copyright &y& Elsevier]