Suppressing harmonic vibrations of a miniature cryogenic cooler using an adaptive tunable vibration absorber based on magneto-rheological elastomers

Abstract

This paper presents dynamic performances of an adaptive tunable vibration absorber (TVA) designed to suppress the main harmonic disturbance of a miniature linear cryogenic cooler, which is being used in space applications such as an observation satellite. The adaptive TVA employs a magneto-rheological elastomer (MRE) for a variable stiffness element. This study first investigates the shear modulus change of MRE samples with respect to the magnetic flux density, which varies through the alignment of particle chains. The MRE with the maximal shear modulus change is mounted for the TVA on a prototype cooler, which emulates the characteristics of a miniature cryogenic cooler. Using the test setup, a series of vibration tests are performed to evaluate the performance and efficacy of the MRE TVA and its re-tuning ability. The experimental results show that the MRE TVA is able to robustly suppress the vibration of the cooler even when the frequency of resonant vibration is changed up to 87% from its initial frequency.

A feasibility study of designing a tunable vibration absorber using stiffness variable magnetorheological gel

“…Beom-Cheol Shin, Jung-Hwan Yoon, Young-Keun Kim*, Kyung-Soo Kim dimension of the material is designed to be applied on the linear compressor used in [12]. The fabricated MRG sample is shown in Figure 1.…”

“…Therefore, in this paper, an MRG TVA is designed and tested to validate the application of the smart material to suppress the unwanted vibration of a linear compressor used in [12]. This paper is organized as follows.…”

Analysis of Electrical Resistance and Impedance Change of Magnetorheological Gels with DC and AC Voltage for Magnetometer Application

“…An external magnetic field is applied to the magnetorheological (MR) materials during the fabrication process to form chain structures of iron particles aligned along the direction of the magnetic field. The internal stress among the chain structures of iron particles is the main factor that causes changes in the viscoelastic properties of MR materials, and this phenomenon is known as the MR effect (MR effect) [4,5,6,7,8].…”

Performance of a semi-active/passive integrated isolator based on a magnetorheological elastomer and spring

“…The bulky and complex nature of the active system makes semi-active isolation as a viable option [5]. In recent years, smart materials have gained much attention for their potential in designing more compact and simpler semi-active isolation systems [6]. 1 Magnetorheological elastomer (MRE), belonging to magnetorheological material family, is a composite material with magnetic-sensitive particles suspended or arranged within non-magnetic elastomer matrix [7].…”