A passive-tuned damper based on magnetorheological porous fabric composite

This paper proposes a novel passive-tuned magnetorheological (PTMR) damper based on developed magnetorheological (MR) porous fabric composite, in which the damping force is tuned by a permanent magnet (PM). Firstly, the influences of the porous fiber structure of composite on the suspended phase are considered, and a continuous constitutive model based on the dipole model is proposed for the first time, which can accurately predict its rheological properties. Subsequently, a stable passive damper for special conditions is designed, and the unique design concept is to achieve completely different damping characteristics for different application scenarios by adjusting the position of the PM relative to the magnetic circuit. The experimental results show that the damping force is relatively stable under specific condition, and can be adjusted within the range of 16.8–77.4 N, with a dynamic range of about 4.6. Moreover, the PTMR damper can exhibit unidirectional negative stiffness characteristic by adjusting the PM to a specific position. The PTMR damper has stable vibration reduction performance, wide dynamic range, and compact structure, which can be comparable to some conventional MR dampers.