PERFORMANCE ANALYSIS OF SMART IMPACT DAMPER SYSTEM USING HERSCHEL-BULKLEY MODEL

摘要

Performance analysis for ER (electrorheological) and MR (magnetorheological) fluid-based impact damper systems is evaluated on the basis of the Herschel-Bulkley shear model. Generally, most ER/MR dampers have been analyzed based on simple Bingham-plastic shear model. However, the Bingham-plastic shear model cannot well describe the behavior of the damper in the condition of high velocity and high field input. Therefore, in this study, the Herschel-Bulkley shear model, in which the constant post-yield plastic viscosity in Bingham model is replaced with a power law model dependent on shear rate, is used to assess performance of ER/MR impact damper systems. In doing so, an ER/MR impact damper system is proposed and its governing equation of motion is derived on the basis of the Herschel-Bulkley shear model. Then, computer simulation is done to analytically evaluate characteristics of the ER/MR impact damper system under impact loads. As an important parameter in the Herschel-Bulkley shear model, effects of the flow behavior index, n, that is the degree of shear thinning or shear thickening, on impact damper system performance are shown.