APRÈN. Portal de la producció docent del professorat de la UPC

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería, módulo de Presentación. https://mooc.upc.edu/

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería, módulo de Dibujo técnico. (https://mooc.upc.edu/)

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería (https://mooc.upc.edu/)

In the framework of building acoustics design, sound propagation between rooms is a major factor in determining the acoustic insulation levels. Acoustic waves can be directly transmitted through common perimetral surfaces or propagate through indirect transmission paths via the building's structure. These indirect transmission paths are the reason why acoustic waves can travel between seemingly unconnected far regions of buildings. The amount of energy the acoustic wave loses when it propagates though a structural junction is quantified with the sound reduction index of that propagation path. In order to determine these indexes, the vibration reduction index of the path between two structural elements that are connected by a structural junction is required. This vibration reduction index is an energetic measure of how different the average displacement values of those two regions are when the structure is oscillating at a determined frequency. Current european regulations have expressions to estimate the vibration reduction index of geometrically simple three-dimensional junctions with extrusion symmetry. In reality, such structures are more complex. Structural junctions are usually delimited by other surfaces and elements that cannot be included in an extrusion symmetry. Existing tables and formulas do not take into account how the geometrical complexity of a 3D environment will affect the vibration transmission between two of its parts. This project will analyse how this geometrical complexity modifies the vibration transmission indexes. A set of three-dimensional cases will be defined and simulated with finite element methods, obtaining the vibration reduction indexes for those specific scenarios. These will be compared with the vibration transmission index of the simplified (extrusion symmetry) version of those cases, which the codes can estimate, in order to analyse whether complete three-dimensional geometries entail a significant difference in the vibratory behaviour.

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería, módulo de Dibujo técnico. https://mooc.upc.edu/

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería, módulo de Dibujo técnico. (https://mooc.upc.edu/)

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería (https://mooc.upc.edu/)

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería (https://mooc.upc.edu/)

Este vídeo forma parte del MOOC El lenguaje de la Ingeniería, módulo de Dibujo técnico. (https://mooc.upc.edu/)

Esta tesina intenta encontrar un procedimiento de resolución optimizada de los sistemas lineales resultantes de la modelización de problemas de propagación acústica de manera que las exigencias de cálculo no se conviertan en un obstáculo insalvable a la hora de solucionarlos. Para ello se ha trabajado con un problema modelo simple que permite una aproximación analítica paralela a la resolución numérica de manera que se puedan extrapolar conclusiones para problemas más complejos. Dicho problema ha sido resuelto para cuatro mallas cada vez más densas que daban pie a matrices de mayor dimensión cada vez..

En aquest projecte s'estudia la connectivitat i l'accessibilitat de l'Aeroport de Barcelona comparant-la amb altres aeroports internacionals i nacionals, depenent de variables com el nombre de rutes, el número de vols i les companyies aèries. Per finalitzar es crearan un seguit de mapes d'accessibilitat i de connexió sobre l'Aeroport de Barcelona per tal de plasmar gràficament els resultats obtinguts de l'anàlisi de les dades.

Problems in the field of vibroacoustics can be modelled in two fundamental ways. On the one hand, they can be addressed in a deterministic way, using numerical methods like the Finite Element Method. On the other hand, statistical methods such as SEA (Statistical Energy Analysis) can be used. Numerical methods are useful for cases with complex geometries but imply a high computational cost for the calculation at high frequencies, especially when working in large domains. They also provide detailed vibration and pressure fields, which are not required by acoustic regulations since they only consider averaged values. Statistical methods are suitable for high frequencies. They deal directly with averaged energies but require specific parameters of power transmission, like internal loss factors and coupling loss factors, whose values can not be calculated analytically for complex geometries. In this work both techniques are coupled so that necessary parameters for the SEA are obtained using a deterministic analysis. In the deterministic approach the Galerkin formulation is used to solve the dynamic problem in its weak form, with the eigenfunctions of the structural elements as the bases of functions used to express the vibration field. Then, a study of the different ways of estimating the coupling loss factor between two subsystems once the deterministic results are obtained is presented, with a discussion of their advantages and disadvantages. The described technique is applied to estimate the coupling loss factors in different configurations consisting of two plates connected with different devices. The obtained results are compared with existing approximated expressions and the good performance of the method is verified. Moreover, the estimated parameters are used to solve larger and more complex systems with SEA. Their results and computational costs are compared with those of the numerical solutions of the same problems. Obtained results differ slightly depending on the technique used for the estimation of the coupling loss factor but provide good trends in general. Therefore, this study shows the potential of combining the deterministic approach (and numerical methods) with the statistical approach in order to solve realistic vibroacoustic problems in the whole frequency range, stressing the differences between the various ways of estimating the coupling loss factor.

El objetivo de esta investigación es desarrollar modelos determinísticos que permitan evaluar el aislamiento frente a ruido de impacto para diferentes tipos de forjados. Estos modelos abordan el problema mediante una aproximación desacoplada. Para ello, primero se modeliza la fuerza aplicada, posteriormente se resuelve el problema estructural y finalmente se calcula la potencia radiada por el forjado, que permitirá obtener los parámetros definidos en la normativa.