Sequential Combustion in Aircraft Propulsion

• Autor(a) principal: Santos, Pedro Miguel Baião
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.6/6397
• topic: Câmara de Combustão Interturbinas.; Combustão Sequencial; Motor Turbofan; Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias

For the past 75 years, technological developments in the fields of materials, aerodynamics, propulsion, computers, electronics and manufacturing, amongst others, as well as the tight control and of government agencies (FAA, EASA) turned the airplane in the most secure and reliable transport in the world, making travel possible to nearly every person and a allowing a fast contact with distant countries. Amongst the innumerous technological developments that allowed the development of the airplane as an indispensable machine for mankind, is the field of propulsion. Changes to the Brayton cycle, the thermic cycle used for gas turbines, allowed lower fuel consumption, less noise and pollution, wider range and increases in thrust, associated to the other fields already mentioned. One of the most important was the concept of Bypass, air that surrounds the core, avoiding the fuel combustion; others already in use were the concept of intercoolers and heat regenerators. Still, as the airplanes grow in size, so do the engines that propel them. One change that has been studied for some years is the concept of sequential combustion: instead of one burner, between the compressors and the turbines, two or more are placed between the different expansion phases of the combustion products, increasing the energy extracted and allowing bigger dimensions for the engine’s components, at the same time reducing the peak combustion temperature. The objective of this study is to apply that change to the Brayton cycle of an existing aero-engine currently used in the civilian market and verify the viability of the concept, in the terms of fuel consumption and thrust.