Simulação de fluidos via Smoothed Particle Hydrodynamics: formulação variacional, variação de parâmetros e extração de características visuais

• Autor(a) principal: Silva, Leandro Tavares da
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações do LNCC
• Texto Completo: https://tede.lncc.br/handle/tede/240
• topic: Funções de Lagrange; Smoothed particle hydrodynamics; Integradores variacionais; Teoria de catastrofes; Sumários de védeo; Lagrangian functions; CNPQ::CIENCIAS EXATAS E DA TERRA::MATEMATICA::ANALISE::ANALISE FUNCIONAL

The Smoothed Particle Hydrodynamics (SPH) is a Lagrangian and meshless method for discretization of fluid equations. It has been used to fluid simulation in many areas of engineering and applied sciences. This method discretizes the Navier-Stokes equations using a particle system and interpolation theory. In this context, we developed a variational integrator to SPH, using the generalized midpoint rule and fixed point method. Then, we elaborate a implementation of SPH to simulate a quasi-incompressible fluid under influence of disks that rotates with constant angular velocity (N-roll mill setup). The obtained flow patterns are analyzed using Morse and Catastrophe theories. Finally, the two aforementioned works show us the necessity of techniques for comparing fluid simulations. Hence, we developed a framework to generate a visual summary of a computation fluid simulations by adapting techniques of video summary areas. As contribution of this thesis we highlight that the variational integrator has the property of linear momentum conservation being easier to implement than counterpart ones. Also, we emphasize the methodology to analyze the critical points generated by the original implementation of N-roll mill setup using SPH. Besides, the pioneer adaptation of techniques in video summarization, for computation fluid dynamics, allows to capture a detailed picture of important segments of the fluid for both comparison and analysis of the flows.