VIBRATION STUDY OF MAGNETORHEOLOGICAL FLUID FILLED SANDWICH BEAMS

International Journal of Applied Research in Mechanical Engineering ◽

10.47893/ijarme.2012.1067 ◽

2012 ◽

pp. 76-80

Author(s):

SHRIKANT B. JOSHI

Keyword(s):

Magnetic Fields ◽

Forced Vibration ◽

Fluid Layer ◽

Research Work ◽

Flexible Structures ◽

Vibration Response ◽

Sandwich Beams ◽

Mr Fluid ◽

Vibration Responses ◽

And Shifts

The concept of vibration mitigation in flexible structures using smart fluids has attracted researcher’s interest in the last few years. Significant research work has been done on the structures with electrorheological fluids, but there has been a little work with the magnetorheological fluids. This study investigates the vibration controllability of MR fluid filled cantilever beams under externally applied magnetic fields. The adaptive structures were fabricated by adding a MR fluid layer between the adjacent elastic layers and the properties of two different types of sandwich beams were studied. In the first type, free and forced vibration responses of aluminium beam with partial treatment were evaluated and compared with fully filled beam. The controllability of vibration response was observed in terms of variations in vibration amplitudes and shifts in magnitudes of the resonant natural frequency. In second type, a composite cylindrical sandwich cantilever beam with end plate was fabricated. It consisted of outer stainless steel hollow pipe with end mass, inner wooden rod and an embedded MR fluid. Inner rods with different diameters were used to vary the thickness of MR fluid layer. Forced vibration response of such beams exhibited increased damping under increased magnetic fields.

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Vibration Localization in Plates With Misplaced Intermediate Supports in Two Orthogonal Directions

Applied Mechanics and Biomedical Technology ◽

10.1115/imece2003-55549 ◽

2003 ◽

Cited By ~ 1

Author(s):

Wei-Chau Xie ◽

Zhihua Chen

Keyword(s):

Forced Vibration ◽

Natural Frequencies ◽

Current Approach ◽

Vibration Response ◽

Vibration Modes ◽

The Finite Element Method ◽

Concentrated Load ◽

Vibration Localization ◽

Vibration Responses ◽

Simple Supports

This paper investigates the effect of small misplacements on both the free vibration modes and forced vibration responses of a four-panel simply supported plate with two intermediate simple supports in two orthogonal directions. Kantorovich’s method is employed to obtain the natural frequencies and the corresponding vibration modes. Galerkin’s method is applied to determine the forced vibration response of the four-panel plate subjected to a harmonic concentrated load at the center of one of its four panels. Comparisons between numerical results obtained using the current approach and those using the exact solution and the finite element method are made to demonstrate the accuracy of the current approach. It is found that the small misplacements of the intermediate supports have dramatic effects on the vibration response of the plate. The larger the misplacement of the intermediate supports, the larger the degree of vibration localization. By judiciously introducing misplacements in the intermediate simple supports, the vibration of some of the four panels may be controlled.

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Analysis of Partially Treated Multi-Layer Beam With Magnetorheological Fluid

Volume 15: Sound, Vibration and Design ◽

10.1115/imece2009-11371 ◽

2009 ◽

Cited By ~ 1

Author(s):

Vasudevan Rajamohan ◽

Ramin Sedaghati ◽

Subhash Rakheja

Keyword(s):

Magnetic Field ◽

Finite Element ◽

Boundary Conditions ◽

Fluid Layer ◽

Transverse Displacement ◽

Mr Fluid ◽

Fluid Layers ◽

Vibration Responses ◽

Magneto Rheological ◽

Finite Element Formulations

The vibration properties of multi-layer beam structure comprising a partial magneto-rheological (MR) fluid layer are investigated to study the influences of size and location of the fluid treatment of the beam. The governing equations for the partially-treated multi-layered MR beam were formulated in the finite element form. The validity of the proposed finite element formulations is demonstrated by comparing the simulation results with those obtained from the Ritz formulation. Two different configurations of a partially treated MR-fluid beam are considered. Simulations are performed to investigate the influences of intensity of an external magnetic field, and the location and length of the MR-fluid layers on the dynamic characteristics of the beam with different boundary conditions. The properties and vibration responses of the partially-treated multi-layer beam are then compared with those of a fully-treated beam. The results suggest that the natural frequencies and transverse displacement response of the partially-treated MR beam are strongly influenced by the location and the length of the fluid pocket, and the boundary conditions, apart from the applied magnetic field.

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Vibration control for a beam structure using an electromagnetic damper with velocity feedback. 1st report Forced vibration response.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.51.3235 ◽

1985 ◽

Vol 51 (472) ◽

pp. 3235-3241

Author(s):

Hiroyuki KOJIMA ◽

Humihiko NIIYAMA ◽

Kosuke NAGAYA ◽

Katsumi NAGAI

Keyword(s):

Vibration Control ◽

Forced Vibration ◽

Vibration Response ◽

Beam Structure ◽

Velocity Feedback ◽

Electromagnetic Damper

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Analysis of vibration response and machining quality of hybrid robot based UD-CFRP trimming

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420986093 ◽

2021 ◽

pp. 095440542098609

Author(s):

Yan Zhang ◽

Hao Li ◽

Xuda Qin ◽

Jie liu ◽

Zhuojie Hou

Keyword(s):

High Performance ◽

Vibration Response ◽

Industrial Robots ◽

Force Characteristic ◽

Surface Waviness ◽

Machined Surface ◽

Machining Quality ◽

3D Surface Roughness ◽

Machined Surface Quality ◽

Vibration Responses

To fulfill the demands of higher precision, better quality, and more flexibility, the usage of high-performance industrial robots is rapidly increased in aerospace industry. Considering the anisotropic and inhomogeneous characteristics of composite materials, this study focuses mainly on dynamic response investigation of a newly designed hybrid robot (named as TriMule) in CFRP trimming process and its influence on the machined quality. First, combined with the cutting force characteristic, the vibration responses of tool center point (TCP) under the dynamic excitation were obtained. The influences of robotic TCP vibration on machined surface quality with different fiber orientations, including surface waviness, cavity, 3D surface roughness, and depth of affected zone, are first studied by comparing hybrid robot and machine tool. From experiment results, it can be concluded the proposed TCP vibration response model has sufficient prediction accuracy. Meanwhile, it is found that larger robotic vibration response is accompanied by higher surface waviness, bigger surface cavity, and greater affected zone. Results also showed that the fiber orientation and milling style are two essential factors that affect robot vibration and machining quality during CFRP trimming.

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Reduction of Forced Vibration Response by Optimum Balance of Linkage and Optimum Design of System

Volume 1A: 16th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc97/vib-4212 ◽

1997 ◽

Author(s):

She-min Zhang ◽

Nobuyoshi Morita ◽

Takao Torii

Keyword(s):

Objective Function ◽

Root Mean Square ◽

Forced Vibration ◽

Vibration Response ◽

New Method ◽

Mean Square ◽

Design Variables ◽

Calculation Results ◽

Angular Velocities ◽

Optimum Balance

Abstract This paper proposes a new method to reduce the forced vibration response of frame of linkage. It is that the root-mean-square (RMS) value of binary maximum (Bmax) of forced vibration response at a series of angular velocities is taken as the objective function, and the counterweight mass parameters of links and the stiffness factors are used as design variables. Then, it is found out that the responses are related not only to the Bmax value of shaking forces, but also to the shape of curve of shaking forces. The calculation results are compared with those of two other methods used in the reduction of forced vibration response by optimized balance of linkages, and it is shown that the new method can significantly reduce the responses of frame of linkage.

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Continuous systems: Forced-vibration response

Dynamics of Structures ◽

10.1201/b11772-25 ◽

2012 ◽

pp. 827-854

Keyword(s):

Forced Vibration ◽

Vibration Response ◽

Continuous Systems

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Effect of Centrifugal Force Effect on Magneto-Rheological Fluid Clutches

Adaptive Structures and Materials Systems ◽

10.1115/imece2002-39012 ◽

2002 ◽

Author(s):

Vijay A. Neelakantan ◽

Gregory N. Washington

Keyword(s):

Magnetic Fields ◽

Design Methodology ◽

Volume Fraction ◽

The Other ◽

Particle Orientation ◽

Centrifugal Forces ◽

Mr Fluid ◽

Set Up ◽

Magneto Rheological ◽

Very High

The property of magnetorheological fluids to change their yield stress depending on applied magnetic fields can be employed to develop many controllable devices one of them being MR fluid based clutches. One major problem however with MR fluid based clutches is that at high rotational speeds, the iron/ferrous particles in the MR fluid centrifuge due to very high centrifugal forces. Thus the particles move outward as the speed increases thereby making the fluid non-homogeneous. Many times however the initial analysis assumes fluid homogeneity, which is really not the case. In this paper this problem is addressed by assuming various volume fraction profiles describing the fluid particle orientation. Two cases, one with a linear profile and the other with an exponential profile are discussed. Expressions for the torque transmitted are derived at for both disc shaped and cylindrical shaped clutches. In addition, the use of a MR sponge based clutch that may indeed reduce the effect of centrifugal forces significantly is described. The design methodology and configuration for the sponge clutch are also discussed. An experimental set up used to test the clutch is also described.

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Thermal and tribological performance of graphite flake based magnetorheological fluid under shear mode clutch

Journal of Tribology ◽

10.1115/1.4051044 ◽

2021 ◽

pp. 1-24

Author(s):

Manish Kumar Thakur ◽

Chiranjit Sarkar

Keyword(s):

Research Work ◽

Magnetorheological Fluid ◽

Tribological Performance ◽

Graphite Flake ◽

Shear Mode ◽

Torque Sensor ◽

Test Rig ◽

Mr Fluid ◽

Mr Fluids ◽

Torque Transmission

Abstract In this research work, graphite flake has been used as an additive in magnetorheological (MR) fluid to improve its thermal and tribological performance. MR fluids with varying amounts of graphite flakes (0.5, 1, 2, 3, 4, and 5 wt%) are prepared to show effective thermal and tribological performance. A test rig is developed with a DC motor, torque sensor, and MR clutch operated in a shear mode to test the torque transmission. Results show the lubrication effects of graphite flakes in MR fluid. Torque transmission is improved in on-state and off-state using graphite flakes based MR fluid as compared to conventional MR fluid. Heating of MR clutch is also reduced with the graphite flakes based MR fluid. Wear marks and damages are decreased significantly with the increased amount of graphite flakes as found in surface roughness tests. SEM and EDS are used to characterize the worn surfaces. This research provides information about the effectiveness of graphite flakes in the MR clutch to improve the device's performance.

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