Análise de escoamento de fluido através de folga em labirinto de canal de turbina Francis por meio de simulação numérica

Abstract

The region located between the rotating and static parts of Francis-type turbines, defined as a labyrinth, demands analysis in relation to the fluid flow through the channels existing at this interface. Due to the complexity of the geometric configurations and the variables involved, the analysis of losses associated with flow in the labyrinth region is a very onerous task. Therefore, the present work aims to evaluate the water flow through the labyrinth clearance in Francis turbines through numerical simulation. The simulations were carried out using the Ansys CFX® software. The discretization of the mass balance and momentum equations was carried out using the finite volume method, and the turbulence model used was the k-ε. The numerical results were compared with analytical solutions used in existing projects and with the analytical method developed in this work. The parameter used for comparisons was the flow rate in the drainage pipe, allowing to conclude that the use of a multiphase simulation model with patch results in flow values aligned with both analytical calculations, indicating the consistency of the work.