Design and analyses of axial semi-active dynamic vibration absorbers based on magnetorheological elastomers

Magnetorheological elastomers are a new kind of magnetorheological materials mainly composed of polymer rubber and micro-sized magnetizable iron particles. Dynamic vibration absorbers based on magnetorheological elastomers are widely used in vibration systems with small amplitude since they have the advantages of no sealing equipments, good stability, and rapid response. In this article, a shear-mode semi-active dynamic vibration absorber based on magnetorheological elastomers is proposed, and the dynamic design principle of an axial semi-active dynamic vibration absorber attached to ship shafting is studied. The material preparation of magnetorheological elastomers and their properties under different magnetic fields are discussed. The structure of a single semi-active dynamic vibration absorber is designed, and theoretical analysis of shift-frequency property of a single semi-active dynamic vibration absorber is also investigated. The magnetic flux density of magnetorheological elastomers in the semi-active dynamic vibration absorber is analyzed using ANSYS software. A compact and efficient semi-active dynamic vibration absorber for shafting axial vibration control is proposed. Furthermore, a linear relationship is found between the excitation current and the natural frequency of a single semi-active dynamic vibration absorber. The results show that the designed axial semi-active dynamic vibration absorbers have better performance than classic passive dynamic vibration absorbers in terms of frequency-shift property and vibration absorption capacity.