Análise de camadas limite turbulentas sobre superfícies rugosas.

• Autor(a) principal: Marsico, Francesco dos Santos
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/11724
• topic: Turbulent Boundary Layers; Surfaces; Engenharia Mecânica; Camada limite turbulenta; Superfícies (Engenharia); CNPQ::ENGENHARIAS::ENGENHARIA MECANICA

The present work uses asymptotic and heuristic arguments to develop a code to optimize the parameters characteristics of boundary layer analysis over surfaces with a sudden change in roughness. The parameters taken experimentally in a wind tunnel are processed and treated to return considered results in a short time. The code uses the concept of displacement in origin and an analogy between the logarithmic laws for the velocity profile. A particular interest of this study is to develop a numeric tool that can be used to describe the velocity s behavior in a boundary layer through a roughness surface. The results are compared with velocity profiles extracted from an experiment settled in a wind tunnel carried out with the propose to validate the new code. Results of friction coefficient, and velocity profiles are resented. The skin-friction coefficient and the error in origin for the velocity profiles was calculated according to the chart methods of Perry and Joubert (1963) and compared with those obtained experimentally. The results are found to be in good agreement. To characterise the self-preserving state, all global parameters characterising the velocity fields are presented, including Clauser factor, momentum thickness, displacement thickness, presenting good agreement.