A simple and efficient passive vibration isolation system for large loads in closed-cycle cryostats

2021 ◽  
Vol 92 (9) ◽  
pp. 095101
Author(s):  
Eugen Wiens ◽  
Stephan Schiller
Keyword(s):  
Vibration Isolation ◽  
Closed Cycle ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Passive Vibration Isolation

scholarly journals Experimental Validation of Fly-Wheel Passive Launch and On-Orbit Vibration Isolation System by Using a Superelastic SMA Mesh Washer Isolator

2017 ◽  
Vol 2017 ◽  
pp. 1-16 ◽  
Author(s):  
Seong-Cheol Kwon ◽  
Mun-Shin Jo ◽  
Hyun-Ung Oh
Keyword(s):  
Vibration Isolation ◽  
Application Form ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Static Tests ◽  
Resolution Observation ◽  
Passive Vibration Isolation ◽  
Basic Characteristics ◽  
Vibration Isolation Performance ◽  
Isolation Performance

On-board appendages with mechanical moving parts for satellites produce undesirable micro-jitters during their on-orbit operation. These micro-jitters may seriously affect the image quality from high-resolution observation satellites. A new application form of a passive vibration isolation system was proposed and investigated using a pseudoelastic SMA mesh washer. This system guarantees vibration isolation performance in a launch environment while effectively isolating the micro-disturbances from the on-orbit operation of jitter source. The main feature of the isolator proposed in this study is the use of a ring-type mesh washer as the main axis to support the micro-jitter source. This feature contrasts with conventional applications of the mesh washers where vibration damping is effective only in the thickness direction of the mesh washer. In this study, the basic characteristics of the SMA mesh washer isolator in each axis were measured in static tests. The effectiveness of the design for the new application form of the SMA mesh washer proposed in this study was demonstrated through both launch environment vibration test at qualification level and micro-jitter measurement test which corresponds to on-orbit condition.

Design of a vibration isolation system using eddy current damper

2013 ◽  
Vol 228 (4) ◽  
pp. 664-675 ◽  
Author(s):  
Partha Paul ◽  
Chetan Ingale ◽  
Bishakh Bhattacharya
Keyword(s):  
Eddy Current ◽  
Vibration Isolation ◽  
Eddy Currents ◽  
High Efficiency ◽  
Experimental Studies ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Analysis And Design ◽  
Passive Vibration Isolation ◽  
Eddy Current Damper

This article aims at modeling, analysis and design of a passive vibration isolation system using a magnetic damper with high efficiency and compactness. The experimental set-up was developed for a single degree-of-freedom vibration isolation system, where the damper consists of two elements: an outer stationary conducting tube made up of copper and a moving core made up of an array of three ring-shaped neodymium magnets of Nd–Fe–B alloy separated by four block cylinders made of mild steel that are fixed to a steel rod. The generation of eddy currents in the conductor and its resistance causes the mechanical vibration to dissipate heat energy. The vibration response of the system is obtained starting from a low-frequency range. The proposed magnetic damper achieves a maximum transmissibility value less than two for a natural frequency that is less than 10 Hz and the excitations at higher frequencies are successfully isolated. Numerical and experimental studies were carried out for a range of system parameters which show that isolators based on magnetic damping could be very effective for passive vibration isolation. Further, a theoretical model for an active isolation system is proposed in order to reduce the transmissibility at resonance. It is envisaged that the combined active–passive eddy current damper could be effectively used for vibration isolation.

Modeling and Simulation of Passive Vibration Isolation System of Combustion Engine with Flexible Base

2012 ◽  
Vol 462 ◽  
pp. 419-426 ◽  
Author(s):  
Guo Qian Zhao ◽  
Hong Tian Zhang ◽  
Rui Guang Geng
Keyword(s):  
Flat Plate ◽  
Vibration Isolation ◽  
Combustion Engine ◽  
Rigid Base ◽  
Vibration Isolator ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Passive Vibration Isolation ◽  
Bearing Force ◽  
Flexible Base

Based on multi-body dynamics, finite element method and solid modeling technology, a dynamic model combined rigid bodies and flexible bodies about passive vibration isolation system of combustion engine with flexible base was built. A simulation analysis was done for a passive vibration isolation system of four-cylinder diesel supported on a flexible flat plate. Simulation result showed static balance and exciting force were same with theory calculation. Through changing support stiffness between flexible flat plate and ground, boundary condition of flexible base could be changed. And the characteristics of vibration isolation were obtained when combustion engine’s flexible base had different stiffness. Compared bearing force of vibration isolator on flexible base with bearing force on rigid base, the results could be gotten that flexible base had important influence to bearing force of vibration isolator and free vibration influenced by base’s flexibility might become main factor to influence change of vibration isolator’s bearing force.

Experimental Study of the Variable Stiffness Vibration Isolator

2011 ◽  
Vol 328-330 ◽  
pp. 2129-2133 ◽  
Author(s):  
Zhi Jun Shuai ◽  
Tie Jun Yang ◽  
Zhuo Liang Zhou ◽  
Zhi Gang Liu
Keyword(s):  
Natural Frequency ◽  
Vibration Isolation ◽  
Excitation Frequency ◽  
Low Frequency ◽  
Variable Stiffness ◽  
Resonance Problem ◽  
Vibration Isolator ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Passive Vibration Isolation

The traditional passive vibration isolation system can reduce the vibration transmission greatly while the excitation frequency is times higher than its natural frequency. As the external excitation approach its natural frequency, vibration isolator system is invalid. In this paper, a new variable stiffness vibration isolator was designed to solve the low-frequency resonance problem of the traditional isolator by combining toothed electromagnetic spring with passive isolator. Theoretical analysis and experimental results illustrate that this isolator met the design requirements and obtained the no resonance operating characteristic at the low frequency.

Study on the Application of Multi-Step Predictive Self-Tuning Arithmetic in Hybrid Isolation System

2009 ◽  
Author(s):  
Shifeng Hu ◽  
Shijian Zhu ◽  
MinJun Zhong ◽  
Qiwei He
Keyword(s):  
Control System ◽  
Vibration Isolation ◽  
Noise Spectrum ◽  
Well Performance ◽  
Isolation System ◽  
Isolation Technique ◽  
Vibration Isolation System ◽  
Radiated Noise ◽  
Passive Vibration Isolation ◽  
Self Tuning

The radiated noise caused by the vibration of the power plant equipment is in the low frequency band and contains discrete lines in the noise spectrum. Insertion of resilient isolators between the machinery and the base is one of the most common methods for controlling unwanted vibration and hence reducing the radiated noise. Passive and active vibration isolation systems have their own relative merits. Therefore, hybrid vibration isolation, a combination of passive and active isolation technique, is a solution to improve the vibration isolation effectiveness. In order to offset the deficiency of passive vibration isolation system of power equipment on ship, the control system of multi-step predictive self-tuning arithmetic in hybrid vibration isolation system was build. The model of the system was obtained and the design of control system was given. And the same time a example of system design was simulated and analyzed. The result showed that the control system of multi-step predictive self-tuning arithmetic in hybrid vibration isolation system can effectively offset the deficiency of passive vibration isolation system and the system have the well performance of robustness.

Researches on Nonlinear Hybrid Vibration Isolation System

2013 ◽  
Vol 823 ◽  
pp. 222-227
Author(s):  
Li Hua Yang ◽  
Jing Jun Lou ◽  
Shi Jian Zhu
Keyword(s):  
Vibration Isolation ◽  
Variable Structure ◽  
Control Model ◽  
Nonlinear Stiffness ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Passive Vibration Isolation ◽  
Practical Engineering ◽  
Nonlinear Hybrid ◽  
Better Than

In this paper, the dynamics of nonlinear hybrid vibration isolation system is carried out for a qualitative analysis, based on the algorithm of synovial variable structure the control model of hybrid vibration isolation system is designed, and then the validity of the control model is verified by relevant examples in the condition of nonlinear stiffness. Moreover, the simulation results show that: the control performance of nonlinear hybrid vibration isolation is better than passive vibration isolation and linear vibration isolation system, and the introduction of nonlinear stiffness can effectively reduce the force transmited to foundation. The control methods studied in this paper has an important guiding significance to design the nonlinear hybrid vibration isolation system in the practical engineering.

Sign in / Sign up

Export Citation Format

Share Document