| Título: | Aeroacoustics of dual-stream jets with application to turbofan engines. |
| Autor: | Odenir de Almeida |
| Programa: | Engenharia Aeronáutica e Mecânica |
| Área de Concentração: | Aerodinâmica, Propulsão e Energia |
| Orientadores : | João Roberto Barbosa |
| Aristeu da Silveira Neto | |
| Ano de Publicação : | 2009 |
| Curso : | Doutorado |
| Assuntos : | Aeroacústica |
| t | Predição de ruído (aeronaves) |
| t | Dinâmica dos fluidos computacional |
| t | Motores Turbofan |
| t | Turbinas a gás |
| t | Ruído aerodinâmico |
| t | Engenharia mecânica |
| t | Engenharia aeronáutica |
| Resumo : | A Computational Aeroacoustics (CAA) and a novel semi-empirical model is developed for predicting the noise generated by the jet flow through dual stream (coaxial) nozzles, as found in modern turbofan engines. The acoustic source model was developed in a 2D and 3D framework, based on the Lilley's Equations, following the traditional MGBK method from NASA Langley Research Center. The semi-empirical model was based on the Four-Source model from the Institute of Sound and Vibration (ISVR). This suite of methodologies provided a mean of investigating the mechanisms of noise generation and propagation of subsonic coaxial jet flows, as well as the noise prediction at different operating conditions. The work done contributed to the development and improvement of a numerical tool for jet noise prediction of dual-stream exhaust systems, commonly employed in turbofan engines. Such research also subsidies the improvement of semi-empirical methods used in the Center of Reference in Gas Turbine (ITA) for the noise prediction of turbofans in all operating conditions. |
| Data de Defesa : | 26/06/2009 |
| Texto na íntegra : | [Visualizar] |