Eventos Anais de eventos
DINAME 2017
XVII International Symposium on Dynamic Problems of Mechanics
TUNABLE AUXILIARY MASS DAMPER WITH FRICTION JOINT: NUMERICAL ASSESSMENT AND PROTOTYPE DESIGN
Submission Author:
HUMBERTO TRONCONI COELHO , MG
Co-Authors:
HUMBERTO TRONCONI COELHO, Francisco Lepore, Marcelo Braga dos Santos
Presenter: HUMBERTO TRONCONI COELHO
doi://10.26678/ABCM.DINAME2017.DIN17-0017
Abstract
Auxiliary Mass Dampers (AMD) are often used to reduce the vibration amplitude of mechanical systems, it is also known that their performances are susceptible to changes in the frequency or in the excitation force’s nature (impulsive, transient, random, periodic). Therefore, to improve the robustness of the AMD it is necessary to design new systems which are adaptable to the excitation, i.e., tunable devices that could be used over large frequency range. In this work a friction damper, which is an association in series of a spring and a scratcher, is used to tune the AMD by changing the normal force on the scratcher, at the same time it dissipates the mechanical energy of the principal mass, this AMD is namely Tunable Auxiliary Mass Damper (TAMD). Three normal force control strategies, and two combinations of them, are studied: i) The normal force is assumed constant; ii) The normal force is obtained from the solution of the equation of motion assuming null displacement for the principal mass; iii) The normal force is obtained based on the vibratory system’s movement, guarantying that the direction of the friction force promotes the movement of the principal mass toward its static equilibrium position. The effectiveness of the proposed TAMD is evaluated based on mass and frequency ratios variations for each strategy. Therefore, the goal is to design a TAMD prototype that meets the design requirements presented in this work and allows obtaining in future work experimental results that proves the device efficiency.
Keywords
Tunable Auxiliary Mass Damper, Variable Damped Absorber, Semi-Active Device Control Strategies, Design of Vibration Attenuation Device, Friction Damper
