Avaliação e implementação de fluxos numéricos eficientes em sistemas magneto-hidrodinâmicos

• Autor(a) principal: Silva, Daniele Pereira da
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/13701
• topic: Magnetohydrodynamic systems; Flux limiter; Numerical fluxes; Sistemas magneto-hidrodinâmicos; Limitador de fluxo; Fluxos numéricos; Análise numérica; Dinâmica dos fluidos - Modelos matemáticos; Métodos de volumes finitos - Métodos de simulação; Geração numérica de malhas (Análise numérica); CNPQ::CIENCIAS EXATAS E DA TERRA::MATEMATICA::MATEMATICA APLICADA

Present work analyzes and develops new methodologies for the improvement of numerical flow calculation in magnetohydrodynamic models (MHD) using finite volume schemes. Flux calculations on discontinuous regions of these equations requires great computational cost, therefore the main focus of this study is the comparison of the computational numerical efficiency of different schemes. We compare the existing approaches in the literature: HLL, HLLD, HLLEM and ROE. We propose a new analysis focusing the improvement of results for discontinuous regions in state and magnetic variables by the introduction of a flow limiter. The new strategy aims the use of schemes that shows a non-increasing total variation when time evolves (TVD criteria). The flow limiters abdquickest, fdherpus, minmod, rus, superbee and vanalba were tested. Results of numerical solution are compared with the analytical solution using a usual MHD problem. Convergence order estimative and computational performance test are presented for the methods and schemes respectively.It is expected that the proposed methodology may be more efficient for numerical flow calculation in MHD systems