Stiffness and damping characteristics of MR fluid-based sandwich beams: experimental study

Abstract

The study investigates the behaviour of three-layered cantilever sandwich beams filled with magnetorheological fluids (MRFs) differing in the iron particle content by volume. Outer layers are made of aluminium, the space between them is sealed with silicone rubber. Two types of beams are considered: fully filled beams and partially filled beams, subjected to the magnetic field. The aim of the study is to determine stiffness and damping characteristics in relation to the magnetic field strength and the actual location where the magnetic field acts upon the beam. For this purpose, measurements have been taken of the beam free vibration response for various magnetic field strength levels and for various positions of the electromagnet located along the beam axis. Basing on the developed measurement data processing algorithm, the influence of the vibration amplitude on the natural frequency and a dimensionless damping coefficient have been determined. Finally, the equivalent natural frequency and the dimensionless damping coefficient have been derived accordingly, and the stiffness and damping ratio have been determined in function of the magnetic field strength, the electromagnet position and the MRF iron particle content by volume.

Applications of Magnetorheological Fluid Actuator to Multi-DOF Systems: State-of-the-Art from 2015 to 2021

“…[4]. Romaszko and Sapinski investigated the dynamic behavior of three-layered cantilever sandwich beams filled with MR fluid with different iron-particle contents by volume [5]. They fabricated two different types of beams, namely, fully filled beams and partially filled beams, and they used free vibration tests to determine that the equivalent natural frequencies and damping coefficients of the beams could be tuned by varying the magnetic field.…”

“…Naji et al studied the vibration behavior of adaptive laminated composite beams integrated with a MR-fluid layer using a modified layer-wise displacement theory in which each layer was modeled based on the first-order shear deformation theory[4]. Romaszko and Sapinski investigated the dynamic behavior of three-layered cantilever sandwich beams filled with MR fluid with different iron-particle contents by volume[5]. They fabricated two different types of beams, namely, fully filled beams and partially filled beams, and they used free vibration tests to determine that the equivalent natural frequencies and damping coefficients of the beams could be tuned by varying the magnetic field.…”

Effect of particle sedimentation on the dynamic properties of magnetorheological sandwich beams

“…30 Romaszko and Sapiński investigated how the position of an electromagnet along the beam's length (assuming the magnet does not span the beam's entire length) contributed to a change in an MR sandwich beam's modal parameters. 31 Sapiński and Snamina studied the merit of implementing a stiffness-switching damping method for MR sandwich beams 20 normally seen in piezeolectric materials, while Romaszko attempted to applies this stiffness-switching damping method on an MR sandwich beam and compared the damping results to those from a constant magnetic field. 32 The authors' own pursuits at MR sandwich beam research began with predicting MR sandwich beam behavior using different models, then eventually implementing using the finite element method.…”

Comparison of semi-active damping strategies for magnetorheological sandwich beams

“…26 Romaszko and Sapiński then investigated the relationship between the MR fluid dynamic properties to the location of the electromagnet along the beam's length. 27 With respect to damping strategies, Sapiński and Snamina explore the concept of switched stiffness, 28 while Romaszko employs that damping method to an MR sandwich beam, though his results suggest that damping is slower than for a constant magnetic field. 29 The authors have also contributed in the area of MR sandwich beam damping.…”