Estudo computacional em poroelasticidade e mecânica dos fluidos

Abstract

This work consists of a computational study in the mechanics of the continuum: applications in poroelasticity and in the study of the influence of buildings on the winds in a coastal zone. A first analysis was performed to verify, through computational models, the influence that empty pores or incrustations in rocks cause on the propagation of mechanical waves. For this, the time in which P and S waves were propagated in a medium with these characteristics was compared when the elastic properties of the scale, such as density and shear modulus, were altered. The numerical resolution of the partial differential equations of the elastic waves using the finite element method using the FEniCS software, whose platform allows the implementation of multi-physics problems, where different differential equations can be solved in the same spatial domain were used as methodology. A set of distinct porosity meshes was created for a two-dimensional domain, where synthetic seismograms were plotted to be analyzed and compared with homogeneous media results. The second part of the research consisted of a study of the wind-building interaction in a region of Fortaleza’s waterfront. Due to population growth in large urban centers, the need for ever-increasing building becomes immediate. This phenomenon can also be seen in tourist regions, where a large number of people are required. This verticalization interferes with the wind flow and can affect the comfort and safety of pedestrians. Another consequence is the reduction of natural ventilation in neighborhoods further away from the sea shore. To better understand this phenomenon, a set of numerical simulations were performed using the OpenFOAM toolbox, where the RANS equations were solved with the turbulence formulated by the k- model. We considered the cases where the winds came from the NNE and SSE directions, with different intensities. The region studied corresponded to an area of 1,6×105 m2. With the results, it was possible to identify the points at which a greater acceleration of the flow, caused by the Venturi effect occurs, besides the mapping of recirculation zones. A vertical velocity profile was also plotted. For winds above 5m/s, a 23% reduction in intensity has been identified at locations 1km away from barriers created by buildings. Curves of energetic turbulent kinetics, turbulent dissipation, and the role of the energetic kinetics along the domain were also plotted.