A vibration absorber incorporating clearance nonlinearity is studied to mitigate the vibration level of an unconstrained structure induced by an impulsive excitation. For such a system, the transient response generally attains its maximum value shortly after the application of the load. It is nearly impossible to control the vibration by dissipating the major portion of the input energy before the occurrence of the peak value of the response. By means of the characteristic momentum exchange phenomenon on a vibro-impact (VI) absorber, we transfer a large portion of the shock energy imparted to the system into the attachment before the maximum vibration occurs. As a result, the peak value can be significantly reduced. In this work, we performed an analysis of the targeted energy transfer in a vehicle subjected to an impulsive excitation in order to mitigate the inertial force imposed on the passenger compartment by using a VI absorber, a form of NES. First, the influence of the VI absorber parameters of attenuation of the maximum inertial force is investigated in detail, based on a practical impulsive force. Both a weak coupling stiffness between the primary structure and the NES and a high coefficient of restitution are found to be favourable for great energy transfer in the initial VI. Then, the optimal design of the VI absorber is obtained, and the maximum inertial force is significantly reduced. Simultation results indicate that an appropriately design VI absorber is more efficient than a conventional TVA for broadband excitations such as impulsive loads. As a side effect of a high coefficient of restitution, however, the vibration response dies out slowly, since the energy dissipation in inelastic impacts depends heavily upon the coefficient of restitution. In an effort to enhance the dynamic performance of the VI absorber, we suggest an asymmetric clearance design for the VI attachment so as to facilitate faster decay rates and, simultaneously, to preserve the attenuation of the maximum inertial force. The feasibility of the proposed scheme is verified, and the results show that such an arrangement can considerably improve the decay rate of the system. In order to test the robustness and efficiacy of the attenuation performance of the VI absorber, an alternate impulsive excitation is applied to the system. The optimal design of the VI absorber parameters for an impulsive force excitation is directly exploited to mitigate the maximum inertial force induced by an impulsive acceleration. Simulation results demonstrate that the VI absorber operates very well for the alternative shock load.
Mitigating the effect of impact loading on a vehicle using an essentially nonlinear absorber
Einflussminderung der Stoßbelastung bei einem Fahrzeug mit prinzipiell nichtlinearem Schwingungsdämpfer
Vehicle System Dynamics ; 47 , 10 ; 1183-1204
2009
22 Seiten, 17 Bilder, 3 Tabellen, 16 Quellen
Aufsatz (Zeitschrift)
Englisch
Schwingungsdämpfer , Anwendung im Fahrzeugbau , Nichtlinearität , Übergangsantwort , Energieübertragung , Stoß (Schlag) , Stoßbeanspruchung , Trägheitskraft , numerische Simulation , mechanische Schwingung , Schwingungsverhalten , Fahrzeugdämpfung , Fahrzeugfahrwerk , Steifigkeit , dynamisches Verhalten , Robustheit
Mitigating the effect of impact loading on a vehicle using an essentially nonlinear absorber
Kraftfahrwesen | 2009
|Mitigating the effect of impact loading on a vehicle using an essentially nonlinear absorber
Online Contents | 2009
|Mitigating the effect of impact loading on a vehicle using an essentially nonlinear absorber
Taylor & Francis Verlag | 2009
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