Banca de QUALIFICAÇÃO: ROSENDO DIOMEDES VELEZ MAMANI

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : ROSENDO DIOMEDES VELEZ MAMANI
Data: 06/11/2026
HORA: 10:00
LOCAL: Sala 303 do Bloco B do Campus de Santo André da Universidade Federal do ABC
TÍTULO:

Vortex-Induced Vibration of Rotating Blades with Flexural–Torsional Coupling Based on Wake Oscillators

PÁGINAS: 80
RESUMO:

The main objective of this master’s research is to develop a computational tool for investigating vortex-induced vibration in rotating blades, including flexural–torsional coupling and modeling the unsteady aerodynamic forces based on wake-oscillator. At this qualification stage, the results obtained do not include torsional effects. These effects will be incorporated in the next stage of the research. The rotating blade is modeled as an Euler--Bernoulli prismatic cantilever beam subjected to small displacements. The geometric stiffness of the blade due to the distributed centrifugal force is also included. The wake oscillator excites the structure through the fluctuating lift force, and the structure responds by exciting the wake oscillator through an acceleration-based coupling term, thus simulating the fluid--structure interaction. The simulations were conducted in the time domain by combining the constant-average-acceleration implicit method for the structural dynamics with the centered finite-difference scheme for the wake dynamics. The computational implementation was verified by reproducing the VIV response reported in literature for a specific blade. Amplitude and frequency responses, together with modal participation and modal energy measures, were obtained for different Strouhal numbers, rotational speeds, free-stream velocities, and wake-oscillator parameters. The response was predominantly governed by the first mode, while sequential modal transitions toward higher modes occurred as the shedding frequency approached the corresponding structural frequencies. These transitions were governed primarily by wake--structure frequency proximity rather than by low-order internal resonance or direct mode-to-mode energy transfer. Variations in the Strouhal number shifted the synchronization regions and modified their peak amplitudes and lock-in widths. Increasing the wake--structure coupling strength increased the vibration amplitude and widened the synchronization regions, whereas the nonlinear wake damping mainly regulated the response amplitude and frequency-capture behavior. Rotational-speed sweeps showed that centrifugal stiffening modifies the structural frequencies and, consequently, the synchronization regions, while increasing and decreasing sweeps revealed hysteretic behavior. The distributed wake-oscillator model allows different local shedding frequencies to be assigned along the blade. With this formulation, synchronization could remain localized or progressively extend along the span toward a nearly global frequency-synchronization state, depending mainly on the degree of spatial detuning, the wake--structure coupling strength, and the proximity between the local shedding frequencies and the structural modes.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1761050 - JUAN PABLO JULCA AVILA
Membro Titular - Examinador(a) Externo ao Programa - 2336809 - CESAR MONZU FREIRE
Membro Titular - Examinador(a) Externo à Instituição - RODRIGO NICOLETTI
Membro Suplente - Examinador(a) Interno ao Programa - 2278416 - MARCELO ARAUJO DA SILVA