Nonlinear modeling of magnetorheological energy absorbers under impact conditions

Abstract

Magnetorheological energy absorbers (MREAs) provide adaptive vibration and shock mitigation capabilities to accommodate varying payloads, vibration spectra, and shock pulses, as well as other environmental factors. A key performance metric is the dynamic range, which is defined as the ratio of the force at maximum field to the force in the absence of field. The off-state force is typically assumed to increase linearly with speed, but at the higher shaft speeds occurring in impact events, the off-state damping exhibits nonlinear velocity squared damping effects. To improve understanding of MREA behavior under high-speed impact conditions, this study focuses on nonlinear MREA models that can more accurately predict MREA dynamic behavior for nominal impact speeds of up to 6 m s−1. Three models were examined in this study. First, a nonlinear Bingham-plastic (BP) model incorporating Darcy friction and fluid inertia (Unsteady-BP) was formulated where the force is proportional to the velocity. Second, a Bingham-plastic model incorporating minor loss factors and fluid inertia (Unsteady-BPM) to better account for high-speed behavior was formulated. Third, a hydromechanical (HM) analysis was developed to account for fluid compressibility and inertia as well as minor loss factors. These models were validated using drop test data obtained using the drop tower facility at GM R&D Center for nominal drop speeds of up to 6 m s−1.

Liquid spring damper for vertical landing Reusable Launch Vehicle under impact conditions

“…The inertance pressure drop [25], [26] can be interpreted as the pressure differential required to accelerate the fluid column located in the flow path. This flow path is represented by the orifice in this work.…”

Design and Analysis of a New Magnetorheological Damper for Generation of Tunable Shock‐Wave Profiles

“…Among them, nonlinear Bingham model showed good performance in shock absorber application [12,21,22]. Accordingly, Bingham model was used in this work.…”

“…Recently, new prediction models for dynamic behavior under high velocity and high frequency conditions have been proposed [11,12]. To account for the behavior of MR damper at high shear rates, Lee et al [11] used the Herschel-Bulkley shear model and Mao et al [12] used a nonlinear Bingham model based on loss factor and hydromechanical analysis.…”

“…To account for the behavior of MR damper at high shear rates, Lee et al [11] used the Herschel-Bulkley shear model and Mao et al [12] used a nonlinear Bingham model based on loss factor and hydromechanical analysis. Ahmadian et al [13][14][15] studied an MR impact damper in gun recoil dynamics and free-flight drop test facilities.…”

“…Browne et al [16] also evaluated the impact damping performance of an MR damper. Although these works focused on the dynamic behavior of MR impact dampers, the maximum damping force range of their proposed MR dampers was relatively low [11][12][13][14][15][16].…”