This report aims to present the different numerical simulations of the model and prototype turbines which were selected to install the AFC4Hydro system, as well as the experimental modal analysis performed to validate those numerical models. In the first section of the document, the geometry of the Porjus U9 reduced scale turbine model is presented. Secondly, the results of a numerical modal analysis of the entire runner and of a single blade are described considering the surrounding water as an infinite domain. Furthermore, the whole shaft line up to the generator has been simulated and validated experimentally in the test rig of Älvkarleby, quantifying the frequencies and damping ratios of the first 4 modes in air and water. Finally, modal analyses of the modified draft tube cone to accommodate the IPM and ICM systems have been performed to avoid the risk of resonances. The following section is devoted to present the numerical results of the Porjus U9 prototype model, which incorporates the different structural elements of the prototype geometry. Firstly, modal analyses of different subcomponents of the turbine have been simulated individually, such as a runner blade or the entire runner. For the shaft line, the periodic rotating forces acting on the runner and the orbits on the generator have also been calculated through a harmonic analysis. Additionally, a validation of the numerical modal analysis of the shaft line has been performed comparing the obtained results with the ones from the experimental modal analysis performed in the full-scale Porjus prototype using the rowing hammer technique. With the validated model, the dynamic response of the shaft line has been computed considering the oscillating forces induced in the runner blades by the hydrodynamic loads of the rotating vortex rope excitation. Finally, modal analyses of the new draft tube cone to accommodate the IPM and ICM systems have also been performed to ensure there is no risk of resonances. Considering the forces and moments induced by the AFC systems on the draft tube cone holes, a structural analysis has also been performed to ensure the integrity of the proposed modifications to allocate the control mechanisms. The electrical, electromagnetic and mechanical performance of the synchronous generator of the Porjus U9 prototype have also been assessed using the ANSYS Maxwell tool RMxprt. The generator has been studied in its flawless operation and compared with the rotor’s non-ideal movement. With these studies, the consequences of the rotor eccentricities have been analyzed to assess if the irregularities in the rotor movement could be observed through any sensor located in a particular position of the generator. With these simulations it has been found that, even though the electrical variables are not significantly altered by the eccentricity, other variables such as the air gap flux density, stator tooth forces and torque waveforms are affected by the eccentricity. In the last section of the document, a numerical model with a geometry similar to the Oksla prototype is presented. With that similar but not exactly equal runner, a numerical modal analysis has been performed and compared with an experimental modal analysis of the real Oksla runner in air.
