Qualitative and quantitative understanding of linear dynamic systems obtained by lumped-mass modeling or finite element modeling. Ability to design mechanical components and structures subject to vibrations. Ability to design damping and insulation systems. Ability to carry out dynamic measurements and identification of linear systems Understanding of limits of linear modeling and basic knowledge of some nonlinear phenomena. Ability to analyze mechanical systems with rotating components.
Dynamics of discrete mechanical systems
Equations of motion, modal analysis, frequency domain representation (FRF), state space representation, numerical integration, discrete time models. Dynamic substructuring, component-mode synthesis, Craig-Bampton method Notes on the response of nonlinear systems (bifurcation, jump, limit cycle) Instability, divergence, flutter
Dynamic response of linear systems with random forcing Review of probability theory, stationary random processes, PSD, self- and cross-correlation, coherence Stationary linear response (spectral analysis), maximum response value, expected frequency, peak factor Dynamics of rotors and rotating elements Free lateral response of rigid rotors on flexible supports, Campbell diagram, synchronous and non-synchronous forces Linear vibrations of elements subject to centrifugal forces (rotor blades), stress stiffening, spin softening Dynamic properties of structures with cyclic symmetry (rotor discs)
Vibration measurement and dynamic identification Review of measurements (AD conversion, sampling, quantization), discrete Fourier transform, aliasing, leakage, windows. PSD and FRF estimate. Experimental modal analysis. Modal identification principles and algorithms, parameterizations of the dynamic system. Operational modal analysis. Structural integrity monitoring tools. Trend identification, envelope estimation (Hilbert transform), identification of pure tones (spectral kurtosis).
Fundamentals of Structural Dynamics. Roy R. Craig, Andrew J. Kurdila
Dynamics of Rotating Machines. Michael I. Friswell, John E. T. Penny, Seamus D. Garvey, Arthur W. Lees
Modal Testing: Theory, Practice and Application. D. J. Ewins
Lecture notes
LUIGI CARASSALE (President)
MASSIMILIANO AVALLE
FLAVIA LIBONATI (President Substitute)
ABDELHAKIM BOURAS (Substitute)
FLAVIA CARONNA (Substitute)
MATTIA FRASCIO (Substitute)
DAVIDE IAFFALDANO (Substitute)
LUDOVICO MUSENICH (Substitute)
ALESSANDRO REBORA (Substitute)
ALESSANDRO STAGNI (Substitute)
https://corsi.unige.it/en/corsi/9269
Oral discussion
Evaluation of knowledge and clarity of presentation through the discussion of the topics covered
