Influência de parâmetros operacionais sobre a eficiência do ciclo Brayton em turbinas a gás estacionárias

• Autor(a) principal: Vieira, Pedro Rafael Lima
• Data de Publicação: 2016
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/38782
• topic: Ciclo Brayton; Brayton cycle; Eficiência; Efficiency; Energia; Energy; Engenharias.

Between the years of 2001 to 2002, Brazil has suffered its greatest energetic crisis due the lack of planning with its hydraulic resources, which lead to the blackouts. The jolt made the country pursuit new kinds of energy sources. Among them stands out the thermoelectric energy, which currently represents 30.3 % of the power supply in Brazil offer, according to the Brazilian monthly bulletin of electrical system monitoring. The process of producing energy through thermoelectric power plants has two main strands (but not only): The power system with the steam turbine and gas turbine. There is also the possibility of having a combined cycle of those two systems. For the system with gas turbine, which is the object of study of this research, the thermodynamics analysis are based on the proposal of a cycle known as Brayton cycle, which has its standard configuration and many other variations that seeks a better thermal efficiency. The effects of operational variables were studied for basic Brayton cycle, non-ideal Brayton regenerative cycle, Brayton cycle with reheating between two turbines in series, Brayton cycle with double compression and inter-cooling and regenerative Brayton cycle with reheating and inter-cooling; in order to investigate the influence of those parameters to work with each of those configurations so that the best efficiency can be achieved. Among the cycles studied, the basic Brayton cycle has shown to be the most peculiar regarding the lack of sensibility when the variables of temperature were changed for the stream entering the process and the stream entering the turbine, maintaining the same efficiency, approximately 44,8%, when modified. The basic Brayton cycle has also been the only to show an efficiency decrease when the pressure were increased in the stream entering the cycle. On the other hand, the Brayton cycle with reheating between two turbines in series was the only one improved when raising the temperature of the stream entering the process. With the data obtained in this research, it was possible to make a rank of the cycles with the best efficiency.