Simulação numérica para avaliação do desempenho de uma bomba centrífuga industrial operando com aletas-guia na tubulação de sucção

Abstract

Studies show that the introduction of guide vanes in the inlet pipe of centrifugal pumps is a method of improving its performance, due to the pre-whirl regulation technique of fluid flow at the impeller inlet. The purpose of the vanes is to reduce the incidence loss at the leading edge of the blades, especially at off-conditions. The purpose of this work is to numerically simulate the fluid flow through the pump impeller, in order to determine the energy gain when inlet guide vanes are used, evaluating the shaft power, the head, the hydraulic power and the efficiency. A study of computational fluid dynamics in hydraulic turbo-machinery, with an emphasis on centrifugal pumps, was elaborated, presenting the fundamentals of fluid mechanics, the turbulent flow modeling techniques, ways of computational mesh generation, the numerical methods for the governing equations discretization, the interface models and the importance of the boundary conditions used. The simulations were based on a experimental study of a centrifugal pump used in the automobile industry to determine the boundary conditions for the CFD study. The numerical results showed good agreement with the experimental data, which validated the developed model. It was possible to evaluate the hydraulic performance of the pump with and without the vanes. The configuration the showed the best performance was the one with the IGV device, which obtained greater energy transfer to the fluid. It was seen that the probability of cavitation occurrence was reduced with the vanes usage. The proposal was considered economically viable, given the energy efficiency gained. The results discussion led to the determination of the study limitations and future projects recommendations.