Abstract:

Elastic systems acted by periodical forces perform vibrations with amplitudes depending on the amplitude of the perturbating force, as well as on its frequency. If the frequency of the perturbating force is close to one of the eigenfrequencies of the elastic system, the oscillation amplitude increases significantly. This phenomenon, called resonance, is particularly important in mechanical engineering, as it can have a negative influence the functioning of the system, may have hazardous effects on the human operator and, in extreme cases, can lead to the deterioration and destruction of the system. A relatively simple method, from the constructive point of view, for avoiding the resonance effect consists in the use of dynamic absorbers. These represent elastic subsystems, which are attached to the main system and which, if properly dimensioned, have as an effect the reduction, up to elimination, of the amplitude of the main mechanical system. The paper presents an educational software application, with graphical interface, which simulates by animation the oscillations of a system with a dynamic absorber. The students can vary the parameters of the system, such as to highlight the effect of the absorber and to determine by a trial-and-error process its optimal characteristics. The software, aimed for use in practical sessions for the courses of mechanical vibrations taught in engineering faculties, will be integrated in a larger virtual laboratory that the authors have developed.

Keywords:

Vibration, damping, dynamic absorbers, simulator.