Study On A Simulation Method Of Variable Mass Dynamic Vibrationabsorber Based On Newmark Algorithm

Dynamic vibration absorber (DVA) is a device used for vibration control. As the band oftraditional dynamic vibration absorber is relatively narrow, the vibration attenuationperformance becomes poor when the excitation frequency changes. Variable mass adaptivedynamic vibration absorber (VM ADVA) is studied in this dissertation, whose naturalfrequency can be adjusted by changing the mass to track the excitation frequency, thus, abetter vibration attenuation performance in wide band will be obtained. Meanwhile, asimulation method based on Newmark algorithm is proposed in order to investigate themotion of the primary system when the DVA mass changes.The main work of this dissertation is as follows:(1) The basic principle of the traditional dynamic vibration absorber, as well as thetheories of the optimum designs based on the displacement response and the accelerationresponse of the primary system, is introduced. The influence of the absorber parameters onvibration attenuation performance is investigated through theoretical derivation. The optimalvibration attenuation theory of the absorber is studied too.(2) Modal superposition methods and step-by-step integration methods for solving thedynamic equation are introduced and the applications of them in solving linear and nonlinearproblems are discussed. Stability and accuracy of several step-by-step integration methodsare analyzed and all work above provides a reference for the selection of the suitablealgorithm.(3) Aimed at the shortcomings of the traditional dynamic vibration absorber, the variablemass dynamic vibration absorber is studied. Its vibration attenuation performance ofbroadband is analyzed too. In order to study the motion characteristics of transient process ofthe primary system, a simulation method based on Newmark algorithm is put forward in thisdissertation.(4) An experimental system was built to study the vibration attenuation performance ofthe VM ADVA. Parameters of the experimental system are identified according to theories ofparametric identification, and the variable mass transient process of the experiment system is simulated by the proposed method. At last, the experimental result is used to verify thecorrectness of simulation method.