Abstract
This paper presents a concept design of Adaptive Tuned Vibration Absorber (ATVA) using a magnetorheological elastomer (MRE) for powertrain transient vibration reduction over a frequency range. The MRE material used to develop the ATVA is a soft MRE whose components are a rubbery silicone polymer matrix and ferrous fillers in fraction of 27.6% by volume. For such a soft MRE the elastic modulus significantly increases due to an external magnetic field. During the transient stage, the powertrain experiences a period of high level vibration because the engine speed passes through one or more its natural frequencies. By using the MRE-based ATVA, the powertrain natural frequencies can be actively tuned either far away the excitation frequency or passed the excitation frequency rapidly as magnetic field speed rather than mechanical manners. Accordingly, global and local tuning methods were proposed for shifting powertrain frequency. Thus, the powertrain transient response could be reduced significantly. Numerical simulations of a powertrain system fitted with the ATVA are used to validate the ATVA proposed design for the transient stage. The obtained results show that when the ATVA is suitably located and properly controlled, the powertrain natural frequencies are shifted away the excitation frequency so that powertrain transient vibration response is significantly suppressed. Also, the effect of ATVA locations to its effectiveness is examined. The ATVA experiment testing will be our next work.
Keywords: dynamic absorber, transient vibration reduction, powertrain vibration, magnetorheological elastomer