Modelagem multifísica de uma unidade geradora hidroelétrica

Abstract

This work is dedicated to the development of a multiphysics model of a hydroelectric generating unit (GU), in which the shaft is represented by finite elements considering a Timoshenko beam with six degrees of freedom per node. The hydrodynamic bearings are modeled by solving the Reynolds equation and the energy equation using the finite volume method. The electromagnetic forces acting on the generator are determined through finite element simulations, solving Maxwell's equations. To represent the hydraulic forces acting on the turbine, results from CFD (Computational Fluid Dynamics) simulations are used, employing the immersed boundary method in conjunction with Large Eddy Simulation. In assembling the complete multiphysics model, with the aim of reducing computational costs and allowing the simulation of various operating conditions, it is opted to represent the supporting forces of the hydrodynamic bearings and the electromagnetic forces of the generator through Kriging surrogates. The multiphysics model is adjusted to represent the generating unit (GU) of Foz do Chapecó, where, upon comparing the vibration amplitudes measured in the GU with the numerical results, a good similarity is observed between them, with errors less than 7%.