Mechanical Vibrations course

Aims of the course

Aim of the course (last academic year: 2004/2005) is providing the essential notions to find out and formulate mathematical models (in terms of lumped systems) and to experiment the vibrational phenomena which are of relevant technical interest in the field of machines and mechanical systems.

Particularly, for these phenomena the necessary elements to model the system are provided, and his mathematical model (in terms of characteristic matrices) is built. Moreover, numeric algorithms and related computer programs are pointed out, in order to calculate the free and forced motion of the system.

Finally, attention is focused on the basis of numerical symulation in regard to the dynamic behaviour of complicated systems, which show linear or not-linear stiffnesses and dampings, and are forced by actions of any kind whatever; the system is modeled by Bond Graph and State equations methods. The numerical symulation is obtained by the CSSP program.

Short list of topics:

• 1 d.o.f. systems: Free and forced vibrations with and without damping.
• Vibrations meters: Vibrometers, accelerometers, strain gauges, vibrations exciters, digital signals analysis.
• 2 d.o.f. systems: Free and forced motion; stiffness and elasticity coefficients; dynamic dampers.
• Vibrations insulation: Active and passive insulation; suspension systems building criteria.
• Multi d.o.f. systems: Motion equations; eigenvalues and eigenvectors; modal analysis; forced motion; constraints free systems; numerical algorithms and related computer programs.
• Dynamics of elastically suspended rigid bodies: Motion equations; [m] and [K] matrices; dynamics of bases and foundations; vehicles suspensions.
• Flexural critical speeds: Constraints of shafts; [A] matrix; rigid and elastic constraints; discs inertia effect; numerical algorithms; the Myklestad method.
• Torsional vibrations: Equivalent systems; forced motion; critical speeds; forced torsional strains.
• Symulation of dynamic systems: State equations; Bond Graph method; multibody systems; the ADAMS program.

Detailed contents (in italian)
Main MD thesys (in italian)




---

Suggested textbooks:

• GUIDO A.R., DELLA VALLE S. - Vibrazioni meccaniche nelle macchine - Liguori, Napoli, 2004
• OLEDZKI A., DE FALCO D., DELLA VALLE S. - Simulazione dinamica dei sistemi fisici - CUEN, Napoli, 1991
• BAYO- DE JALON - Kinematics and Dynamic Simulation of Multibody Systems