A numerical research with different turbulence models for shallow water equations was carried out. This was done in order to investigate which model has the ability to reproduce more accurately the wakes produced by the shock of the water hitting a submerged island inside a canal. The study of this phenomenon is important for the numerical methods application advancement in the simulation of free surface flows since these models involve a number of simplifications and assumptions that can have a significant impact on the numerical solutions quality and thus can not reproduce correctly the physical phenomenon. The numerical experiments were carried out on an experimental case under controlled conditions, consisting of a channel with a submerged conical island. The numerical scheme is based on the Eulerian-Lagrangian finite volume method with four turbulence models, three mixing lengths (ml), and one joining -on the horizontal axis with a mixing-length model (ml) on the vertical axis. The experimental results show that a -with ml turbulence model makes it possible to approach the experimental results in a more qualitative manner. We found that when using only a -model in the vertical and horizontal direction, the numerical results overestimate the experimental data. Additionally the computing time is reduced by simplifying the turbulence model.

This work is focused on studying interface waves for three canonical models, that is, interfaces formed by vacuum-solid, solid-solid, and liquid-solid. These interfaces excited by dynamic loads cause the emergence of Rayleigh's, Stoneley's, and Scholte's waves, respectively. To perform the study, the indirect boundary element method is used, which has proved to be a powerful tool for numerical modeling of problems in elastodynamics. In essence, the method expresses the diffracted wave field of stresses, pressures, and displacements by a boundary integral, also known as single-layer representation, whose shape can be regarded as a Fredholm's integral representation of second kind and zero order. This representation can be considered as an exemplification of Huygens' principle, which is equivalent to Somigliana's representation theorem. Results in frequency domain for the three types of interfaces are presented; then, using the fourier discrete transform, we derive the results in time domain, where the emergence of interface waves is highlighted.

acústico (fluido) en contacto con un medio sólido elástico, para una gama amplia de materiales sólidos. Se ha demostrado que mediante un análisis de ondas difractadas en un fluido, es posible inferir las propiedades mecánicas del medio sólido elástico, específicamente, sus velocidades de propagación. Con este fin, el campo difractado de presiones y desplazamientos, debido a una onda de presión inicial en el fluido, son expresados empleando representaciones integrales de frontera, las cuales satisfacen la ecuación de movimiento. La fuente en el fluido es representada por una función de Hankel de segunda especie y orden cero. La solución a este problema de propagación de onda es obtenida por medio del Método Indirecto de Elementos Frontera, el cual es equivalente al bien conocido teorema de representación de Somigliana. La validación de los resultados se lleva a cabo usando el Método del Número de Onda Discreto y el Método de Elementos Espectrales. Primeramente, presentamos espectros de presiones que ilustran el comportamiento del fluido para cada material sólido considerado, después, mediante la aplicación de la Transformada Rápida de Fourier se presentan resultados en el dominio del tiempo, mediante simulaciones numéricas que muestran la emergencia de las ondas de Scholte.Palabras clave: propagación de ondas, interfases fluidas-sólidas, ondas de Scholte, elementos frontera, ondas de interfaz, Funciones de Green.

The present paper shows the applicability of the dual boundary element method to analyse plastic, viscoplastic and creep behaviours in fracture mechanics problems. Several models with a crack, including a square plate, a holed plate and a notched plate, are analysed. Special attention is taken when the discretization of the domain is performed. In fact, for the plasticity and viscoplasticity cases, only the region susceptible to yielding was discretized, whereas the creep case required the discretization of the whole domain. The proposed formulation is presented as an alternative technique to study these kinds of nonlinear problems. Results from the present formulation are compared to those of the well‐established finite element technique, and they are in good agreement. Important fracture mechanic parameters like KI, KII, J‐integrals and C‐integrals are also included. In general, the results, for the plastic, viscoplastic and creep cases, exhibit that the highest stress concentrations are in the vicinity of the crack tip and they decrease as the distance from the crack tip is increased.

A matrix formu la tion to study the coupled response of rigid foun da tions modelled by springs and dashpots is presented. Springs and dashpots orien ta tion can be any possible, thus a general solu tion is deter mined. Response in terms of displacements and rota tions is deter mined from a matrix system in the complex field. The physics of the problem presented here has been exten sively studied and a broad range of useful formulas to deter mine springs and dashpots prop er ties in soil-struc ture inter ac tion is avail able, however it has also been iden ti fied that there are some limi ta tions on coupling various degrees of freedom in the avail able formu la tions. Then, the novelty of the approach presented comes from the matrix manip u la tion that leads to an expres sion that provides a closer approx i ma tion to the real phenom enon, because all degrees of freedom can be coupled. This approach may allow to the analyst finding a coupled response including the cases when either springs or dashpots are not orthogo nally oriented. In an example at the end of this study, the influ ence of one of the involved param e ters in the soil-struc ture anal ysis is point ed out.