PERFORMANCE OF PARTICLE DAMPERS UNDER RANDOM-EXCITATION

An experimental and analytical study is made of the performance of par ticle dampers under wide-band random excitation. A small model, provid ed with a nonlinear auxiliary mass damper, was used to investigate the major system parameters that influence the performance of particle da mpers: total auxiliary mass ratio, particle size, container dimension, and the intensity and direction of the excitation. it is shown that p roperly designed particle dampers, even with a relatively small mass r atio, can considerably reduce the response of lightly damped structure s. An approximate analytical solution, which is based on the concept o f an equivalent single unit-impact damper is presented. It is shown th at the approximate solution can provide an adequate estimate of the ro ot-mean-square response of the randomly excited primary system when pr ovided with a particle damper that is operating in the vicinity of its optimum range of parameters.