Análise da geometria do difusor em ejetores de superfície instalados em poços de petróleo

• Autor(a) principal: Varela, Neyla Karolinne Laurentino
• 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/123456789/39524
• topic: Ejetor; CFX; Dimensionamento; Ângulo; Difusor; Ejector; Design; Angle; Diffuser

Ejectors are equipment that operate using kinetic energy of a moving fluid generated due to its high speed to pump a secondary fluid. At the depth of some wells such as, for example, those using pumped artificial elevation methods, gas separators are placed to guide them to the annulus in order to reduce the damage that gas can cause. From there, comes a new problem which can also be derived from a high gas-liquid ratio (GLR), the accumulation of gas in the annulus, increasing flow pressure of the reservoir, and consequently decreasing production of the well. One way to reduce this problem is to attach the casing to the flow line through a check valve. This valve operates through differential pressure, allowing passage only in the casing-flow line direction, which occurs when the line pressure is lower than that of the annulus. In an attempt to reduce the annular pressure to lower values than the line pressure, it is possible to connect an ejector to the wellhead, increasing their production due to realization of the trapped gas suction in the annulus that causes the reduction in casing pressure. The Well Head Ejector (WHE), software developed by students of Universidade Federal do Rio Grande do Norte (UFRN) for the design of oil-gas ejectors, assisted define the geometry to be used in the CFX simulations to analyze the best angle of diffuser inclination and, consequently, their length, without changing the diameter of the throat and of the diffuser's output diameter. By analyzing the behavior of the gas volumetric fraction, the flow lines and the pressure and velocity graphs along the ejector, it was concluded that the best behavior was the diffuser with the lowest divergence angle among the studied ones.