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This paper describes a new simplified model for controller design of open water channels that are relatively short, flat and deep: the integrator resonance model (IR model). The model contains an integrator and the first resonance mode of a long reflecting wave. The paper compares the integrator resonance model to the simplified models: integrator delay, integrator delay zero and filtered integrator delay and to the high-order linearized Saint-Venant equations model. Results of using the integrator resonance model in a model predictive controller applied in closed loop on a high-order non-linear Saint-Venant model of the first pool of the laboratory canal at Technical University of Catalonia, Barcelona are compared to the results of using the other simplified models in MPC. This comparison shows that the IR model has less model mismatch with the high order model regarding the relevant dynamics of these typical channels compared to the other simplified models. It is demonstrated that not considering the resonance behavior in the controller design may result in poor performance of the closed loop behavior. In order to demonstrate the validity of the simulation model used in this study, the controller using the IR model is also tested on the actual open water channel and compared to the results of the high-order non-linear Saint-Venant simulation model. The results of this comparison show a close resemblance between simulation model and real world system. (C) 2014 Elsevier Ltd. All rights reserved.

This text addresses the particular case of motion and causes of motion of granular material as bedload in the fluvial domain. The aim is to perform and overview of key concepts, main achievements and recent advances on the description of the processes involved in erosion, deposition and transport of sediment in open-channels. The theoretical functional relations describing both the initiation of motion and the sediment transport are introduced. The classical problem of the initiation of motion of particles is treated at grain and at reach scales, accounting for the stochastic nature of flow. Concepts of granular kinematics and methods for quantifying the sediment transport rate in rivers are presented. The latter results from the interactions between the flow and the particles on the bed surface. The sediment transport rate, which has been shown to have a stochastic behaviour, is converted to a lumped statistic distribution. Finally, some field and laboratory techniques for measuring sediment transport, accounting for its inherent fluctuations, are introduced.

A slender body theory method developed for a body moving parallel to a wall in shallow water is extended to include angular orientation of the body to the wall. The method satisfies only the zero normal velocity condition on the external boundaries but does not take into account the effect of induced flows on the body itself. A spheroid and a Series 60, block .80 hull were the bodies studied. The side force and yaw moment on each body were determined numerically for varying angular orientation with respect to either a single wall or canal bank. For both cases results for a range of depths and wall separation distances are presented. It is found that the method gives good qualitative side force predictions for a body moving parallel to a wall, but is unable to correctly predict the yaw moment or the side force due to angular orientation. This result dictates the need for a more complex mathematical model to properly represent the flow than the simple model and quasi'steady method used here. Master of Science

En aquest treball es tractarà de resoldre una qüestió no regulada per la ITTC; l’amplada mínima necessària en un canal hidrodinàmic per tal d’evitar l’efecte de bloc. Aquest efecte de bloc, causat pel rebot de les onades de l’estela en les parets del canal, produïdes pel model d’embarcació en el seu pas pel canal, pot interferir en l’estudi del model a analitzar. Les proves realitzades fins a l’actualitat han tractat de pal•liar aquest efecte amb coeficients de compensació i formules aproximades, en relació amb l’eslora del model o la profunditat del canal. Durant aquest treball s’exposaran les diferents solucions utilitzades fins la data d’avui, tractant de posar en context la necessitat d’aquesta investigació i es tractarà de resoldre aquesta qüestió gràcies a les eines CFD mitjançant el programa SeaFEM. Aquest procés es reproduirà a través d’una sèrie de simulacions del comportament de les onades per a diferents amplades de canal per a un mateix model d’embarcació. L’objectiu d’aquest estudi és trobar una relació entre màniga del model i ample del canal, per delimitar amb exactitud l’escala mínima d’ús en assajos de resistència a l’avanç en canal.

Para las olimpiadas de Barcelona de 1992 se necesitaron una serie de notables infraestructuras, entre las que figuraba un canal de remo de dimensiones apropiadas. Se barajaron diferentes posibilidades y se decidió construirlo en el sector occidental del Delta del Llobregat por excavación de las arenas superficiales, dejando que fuese el agua subterránea freática la que llenase el espacio vaciado. Se describen los estudios previos realizados con carácter de urgencia y el seguimiento de la excavación, con sus efectos hidráulicos y la calidad del agua drenada. La infraestructura, dadas sus notables dimensiones, tiene un impacto sobre la hidrogeología local, por efecto de drenaje durante la excavación, por suponer un cortocircuito en condiciones de piezometría espacialmente variable y por el incremento de evaporación. A pesar de la urgencia de la actuación se estudiaron las diferentes alternativas propuestas para evitar un elevado coste y minimizar las afecciones al medio ambiente y terceros.

En los últimos años se ha amplificado el uso de herramientas de fabricación digital, con la aparición los fablabs y la mejora notable de las impresoras 3D ha sido posible la realización de nuevos proyectos, siendo estos más accesibles al usuario y facilitando la producción y generación de creaciones ya sean experimentales o personales. Es una herramienta que se puede utilizar para usos educativos, mejorando la interacción entre el estudiante y sus ideas creativas, de esta forma se puede plasmar a la realidad obras que quizá años atrás no hubiera sido posibles llevarlas a cabo. Actualmente existen multitud de sistemas y equipos de medida e instrumentación para la medida de calado o caudal para ensayos de laboratorio o medidas in situ en el campo, para muchos de ellos se necesita un elevado presupuesto para ser adquirirlos y asimismo muchos son específicos solo para proporcionar datos de una variable. Además de requerir sistemas externos para poder recoger, almacenar lecturas o poder visualizar los resultados a tiempo real. La idea principal del presente trabajo es el desarrollo de herramientas low-cost para la medición de calado en el canal hidráulico situado en el Laboratori d’Hidràulica de la Escola Tècnica Superior d’Enginyers de Camins, Canals y Ports de Barcelona.Se iniciará el estudio con varias pruebas in-situ en el canal, cambiando las condiciones de contorno y analizando los resultados obtenidos. Para llevar a cabo el estudio primeramente se hizo un análisis general de los distintos instrumentos que existen actualmente para el cálculo del calado en un canal o rio, analizando las características y de esta forma poder conocer más detalladamente cuales son las carencias de cada uno y como poder solventarlas. De forma que el marco general de este proyecto es desarrollar un sistema de medida de calado a través de herramientas de fabricación digital. Para la elaboración del proyecto se hace uso de Arduino, plataforma electrónica de código abierto, cuenta con Hardware y Software donde el entorno de desarrollo y su lenguaje son sencillos de usar, con la necesidad de tener una base de programación elevada. Otro de los programas utilizados es Processing, permitiendo generar una animación del canal hidráulico simulando un sistema de partículas fluyendo por el agua. Asimismo se hizo uso de impresora 3D, y de otros software como Fritzing y FreeCAD. Señalar que el trabajo realizado se ha procedido de forma que los resultados obtenidos son experimentales, se hicieron las distintas calibraciones y validaciones de los sensores, se estudiaron primero individualmente en zonas externas al canal, una vez conocidos y comprobado que los códigos funcionaban se actuó en el Laboratorio. Es decir, se han hecho verificaciones de los resultados pero no dejan de ser valores empíricos. In recent years the use of digital manufacturing tools has increased, with the apparition of fablabs and the major improvement of 3D printers, it has been possible to realize new projects, being these more accessible to the user and facilitating the production and the generation of creations weather experimental or personal. It’s a tool that can be applied in educational purposes, improving the interaction between the student and his creative ideas, applying this method they can bring to life ideas that years ago would have not been possible to carry them out. There are currently many systems and measuring equipment and instrumentation for the measurements of draught or flow for laboratory tests or measures in situ in the field, for many of them it takes a high budget to be acquiring them and many are also specific only to provide a variable data. In addition to requiring external systems to collect, store readings or visualize the results in real time The main idea of this work is the development of low cost tools for the measurement of draught in the hydraulic canal located at the Laboratori d’Hidràulica of the Escola Tècnica Superior d’Enginyers de Camins, Canals y Ports de Barcelona. Se start the study with several tests on-site in the channel, changing boundary conditions and analyzing the results obtained. To carry out the study a general analysis was done to the different equipment that actually exists for the measuring of draught canal or rivers, analyzing the characteristics to have a deeper and detailed analysis to know each characteristic and how to solve any issues. As this project is to create a measurement system of draught using digital tools. For making the Project is utilized Arduino, electronic platform of open code, relies on with Hardware and Software where the environment of development and it’s language are simple to use, without needed to have a base of high programming. Other of the used program is Processing, allowing to generate animations of the hydraulic channel, simulating a particle system flowing for the water. In addition, one made use of printer 3D, other software as Fritzing and FreeCAD. Point out that the work has proceeded in such a way that the results obtained are experimental, became different calibrations and validations of the sensors, they studied first individually in areas external to the channel, once known and proven that the codes worked he performed in the laboratory. I.e. verifications of the results have been made but never cease to be empirical values.

This chapter reviews the basic principles of sediment transport in streams, channel classification, mountain channel morphology, and associated implications for fish spawning habitats. Local sediment transport processes construct the differing channel morphologies, which are often opportunistically used by spawning fish. Sediment load in streams can be transported in various ways. Dissolved load corresponds to material transported in solution with the fluid, whose concentration depends primarily on the geochemical character of basin geologic materials, and the dissolution of these materials by groundwater flow. Sediment sources in river basins can be distinguished as two types for timescales ranging from individual floods to many flood seasons. Sediment resting on the streambed will move, or become entrained, when the overlying fluid pressure, or shear stress, exceeds some threshold value. Lumped empirical or semi-empirical expressions have been widely used to compute bedload transport rates. Sediment transport and channel morphology are important components of physical habitat for aquatic biota in rivers.