Experimental Analysis of MR Fluid by Magneto-Rheological (MR) Damper

2015 ◽  
Vol 813-814 ◽  
pp. 1002-1006 ◽  
Author(s):  
P. Thirupathi ◽  
Perumalla Janaki Ramulu ◽  
S. Venukumar ◽  
Peddabavi Saikiran Reddy ◽  
B. Krishna Reddy ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Mr Damper ◽  
Viscous Fluids ◽  
Lubricating Oil ◽  
Distilled Water ◽  
Iron Particles ◽  
Mr Fluid ◽  
Damping Effect ◽  
Piston Head ◽  
Magneto Rheological

Magneto-rheological fluids belong to a group of non-Newtonian fluids, and represent a group of purely-viscous fluids with the controllability of their properties by means of a magnetic field. In the present work, MR damper setup has designed and fabricated. MR fluid is prepared by mixing the lubricating oil, distilled water and iron particles of size 500 meshes in the standard proportions. During the experimentation, arrangement is made for load which falls on the piston head of MR damper to determine the damping effect. For every reputation, time and displacement of piston in the MR fluid is noted. Based on these parameters, velocity of the piston and rate of acceleration with respect to time and acceleration with respect to displacement is determined. Damping effect is calculated by using acceleration with respect to time and displacement respectively.

A New Unified Approach for Flow Analysis of Magneto-Rheological Fluids

Aerospace ◽  
2004 ◽  
Author(s):  
Barkan M. Kavlicoglu ◽  
Faramarz Gordaninejad ◽  
Xiaojie Wang ◽  
Gregory Hitchcock
Keyword(s):  
Magnetic Field ◽  
Surface Roughness ◽  
Pressure Loss ◽  
Flow Analysis ◽  
Volumetric Flow Rate ◽  
Mr Fluid ◽  
Mason Number ◽  
Universal Approach ◽  
Shear Yield ◽  
Magneto Rheological

The focus of this study is to develop a new universal approach for the flow analysis of magneto-rheological (MR) fluids through channels. An experimental study is conducted to investigate the relationship between the pressure loss of a MR fluid as a function of the applied magnetic field strength, volumetric flow rate, and surface roughness without utilizing the assumption of shear yield stress. A relation for nondimensional friction factor is developed in terms of Mason number and dimensionless surface roughness. It is demonstrated that the pressure loss across the MR fluid flow channel is significantly affected by the magnetic field and the surface roughness.

Magneto-Rheological (MR) Damper Design for High-Flowrate Suspensions

2013 ◽  
Author(s):  
Riaan F. Meeser ◽  
P. Schalk Els ◽  
Sudhir Kaul
Keyword(s):  
Mr Damper ◽  
Damping Force ◽  
Mr Fluid ◽  
Bingham Plastic ◽  
Damping Characteristics ◽  
Final Design ◽  
Variable Damping ◽  
Input Variables ◽  
Damper Design ◽  
Magneto Rheological

This paper presents the design of a magneto-rheological (MR) damper for an off-road vehicle where large suspension travel and high flow rates, as compared to typical passenger car suspensions, are required. The MR damper is expected to enhance the capability of the suspension system by allowing variable damping due to inherent properties of the MR fluid. MR fluids exhibit a reversible behavior that can be controlled with the intensity of a magnetic field, allowing a change in the effective viscosity and thereby in the damping characteristics of the fluid. A mathematical model of the proposed damper has been developed using the Bingham plastic model so as to determine the necessary geometry for the damper designed in this study, using the fluid flow rate and current to the electromagnet as the input variables. The model is used to compute the damping force, and the analytical results show that the designed MR damper provides the required range of damping force for the specific vehicle setup that is being used for this study. A valve-mode MR fluid channel has been designed such that the required minimum damping is reached in the off-state, and the desired maximum damping is reached in the on-state. For manufacturing and size considerations, the final design incorporates a triple pass layout with the MR fluid flowing through the three passages that are arranged in an S-shape so as to minimize the cross section of the electromagnet core.

PREPARATION AND ABRASION PROPERTIES OF MAGNETO-RHEOLOGICAL FLUID OF DISPERSED SILICA-COATED IRON

2005 ◽  
Vol 19 (07n09) ◽  
pp. 1121-1127 ◽  
Author(s):  
A. SHIBAYAMA ◽  
T. OTOMO ◽  
Y. AKAGAMI ◽  
K. SHIMADA ◽  
T. FUJITA
Keyword(s):  
Carbonyl Iron ◽  
Spherical Particles ◽  
Fluid Viscosity ◽  
Iron Particles ◽  
Mr Fluid ◽  
Abrasion Test ◽  
Silicon Oil ◽  
Mr Fluids ◽  
Transmission Oil ◽  
Magneto Rheological

In this study, a magneto-rheological fluid dispersed by silica-coated iron was developed and its properties such as fluid viscosity (shear stress or shear rate) and abrasion were investigated. The metallic iron coated by silica dispersed in magneto-rheological fluid was prepared by H 2 reducing of precipitated magnetite ( Fe 3 O 4). Then, the magneto-rheological fluid (MR fluid) for the seal was prepared with silica-coated iron or carbonyl iron (HQ type; diameter of 1.6-1.9 10-6m) and two solvent oils i.e. silicon oil (SH200cv, 10000cSt) and CVT oil (T-CVTF, automobile transmission oil). It was observed that the MR fluid viscosity of CVT oil with HQ particles is lower in every fluid condition. Furthermore, the surface roughness of polyvinyl plate after abrasion test for MR fluid with silica coated iron and CVT oil as solvent was higher compared to the other types of MR fluids. The results indicated that carbonyl iron (spherical particles) and silica-coated iron particles dispersed in silicon oil are feasible to be used where the low abrasion in mechanics is required.

The Effect of Particle Concentration and Magnetic Field on Tribological Behavior of Magneto-Rheological Fluid

2011 ◽  
Vol 314-316 ◽  
pp. 58-61 ◽  
Author(s):  
Wan Li Song ◽  
Chul Hee Lee ◽  
Seung Bok Choi ◽  
Myeong Woo Cho
Keyword(s):  
Magnetic Field ◽  
Friction Coefficient ◽  
Wear Mechanism ◽  
Particle Concentration ◽  
Tribological Behavior ◽  
Wear Loss ◽  
Wear Properties ◽  
Mr Fluid ◽  
Magneto Rheological ◽  
The Magnetic Field

In this paper, the effect of particle concentration and magnetic field on the tribological behavior of magneto-rheological (MR) fluid is investigated using a pin-on-disc tribometer. The wear loss and friction coefficient are measured to study the friction and wear properties of MR fluid. The morphology of the worn pin is also observed by scanning electron microscope (SEM) in order to analyze the wear mechanism. The results obtained in this work show that the wear loss and friction coefficient decrease with increasing particle concentration under the magnetic field. Furthermore, it is demonstrated that the magnetic field has a significant effect on improving tribological properties of MR fluid, especially the one with high particle concentration. The predominant wear mechanism of the MR fluid has been identified as abrasive wear.

scholarly journals Study of failure symptoms of a single-tube MR damper using an FEA-CFD approach

2020 ◽  
pp. 1045389X2096983
Author(s):  
Wael Elsaady ◽  
S Olutunde Oyadiji ◽  
Adel Nasser
Keyword(s):  
Magnetic Field ◽  
Mr Damper ◽  
Numerical Approach ◽  
High Viscosity ◽  
High Yield ◽  
Air Bubbles ◽  
Element Analysis ◽  
Mr Fluid ◽  
Mr Dampers ◽  
Flow Parameters

A new magnetorheological (MR) damper has been designed, manufactured, modelled and tested under cyclic loads. A faulty behaviour of the damper was accidentally detected during the experiments. It was deduced that the presence of air bubbles within the MR fluid is the main reason for that failure mode of the damper. The AMT-Smartec+ MR fluid used in the current study, a new MR fluid whose characteristics are not available in the literature, exhibits good magnetic properties. However, the fluid has a very high viscosity in the absence of magnetic field. It is assumed that this high viscosity enables the retention of air bubbles in the damper and causes the faulty behaviour. To prove this assumption, a coupled numerical approach has been developed. The approach incorporates a Finite Element Analysis (FEA) of the magnetic circuit and a Computational Fluid Dynamics (CFD) analysis of the fluid flow. A similar approach was presented in a previous publication in which an ideal behaviour of an MR damper (no effect of air bubbles) was investigated. The model has been modified in the current study to include the effect of air bubbles. The results were found to support the assumptions for the reasons of the failure symptoms of the current MR damper. The results are shown in a comparative way between the former and current studies to show the differences in flow parameters, namely: pressure, velocity and viscosity, in the faultless and faulty modes. The results indicate that the presence of air bubbles in MR dampers reduces the damper force considerably. Therefore, the effect of the high yield stress of MR fluids due to the magnetic field is reduced.

Analysis of Magneto Rheological Fluid Journal Bearing

2019 ◽  
Vol 895 ◽  
pp. 152-157 ◽  
Author(s):  
B. Narasimha Rao ◽  
A. Seshadri Sekhar
Keyword(s):  
Magnetic Field ◽  
Newtonian Fluid ◽  
Carrying Capacity ◽  
Smart Materials ◽  
Journal Bearing ◽  
Fluid Film ◽  
Load Carrying Capacity ◽  
Mr Fluid ◽  
Load Carrying ◽  
Magneto Rheological

Magneto Rheological (MR) fluids are a class of smart materials where the shear stress is not directly proportional to rate of shear. The viscosity of fluid changes as magnetic field changes and hence this phenomenon is very useful in bearing-rotor system for attenuating the vibrations. In the present study the application of MR fluid as lubricant instead of Newtonian fluid in the journal bearing is explored through steady state, dynamic characteristics and stability. MR fluid film has been modeled as per Bingham rheological model. FEM with three node triangular elements has been used to solve the Reynolds equation both for the Newtonian fluid film and MR fluid film. The results show the load carrying capacity in the case of MR fluid journal bearing is higher than that of using the Newtonian fluid. The load carrying capacity increases with the increasing magnetic field for all eccentricity ratios. The results also show better stability of the bearing using MR fluid at higher eccentricity ratios. The unbalance response of the rotor mounted on the journal bearing using MR fluid is also estimated to be lower than that of with the Newtonian fluid.

Performance of silicon oil-based Magneto-Rheological fluids used for MR dampers: an experimental approach

2021 ◽  
Vol 13 ◽  
Author(s):  
Mohamed Bakr ◽  
Tamer Nabil ◽  
Ali Eldomuaty ◽  
Tamer Mansour ◽  
Hossam Hammad ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Particles ◽  
Silicone Oil ◽  
Spherical Shape ◽  
Magnetic Behavior ◽  
Power Requirement ◽  
Mr Fluid ◽  
Lithium Grease ◽  
Working Temperature ◽  
Magneto Rheological

Aim: The aim of this work was preparation of the model Magneto Rheological (MR) fluids to be used under the effect of an applied magnetic field operated under very low power requirement for the purpose of vibration reduction in automotive damper. Background: Magneto-Rheological fluids are non-Newtonian fluids, which consist of magnetic particles scattered in a base liquid – a matter that can change their characteristics when applying the magnetic field. From the previous researches, Magneto-Rheological fluids have different properties according to the preparation accuracy, ingredients, particle size and shape, type of carrier fluids and stabilizer. Also, the response of Magneto-Rheological fluids to the magnetic flux varied. Methods: : A specimen of MR fluid is prepared using four different dynamic viscosities base fluids: Silicone oil JETTA (50mpa.s, 100mpa.s, 150mpa.s and 200mpa.s) are mixed with high purity spherical shape particles of Carbonyl Iron (CI). ABRO liquid white lithium grease is added to the specimen, and its effect is determined. Results: The presence of additives has no effect on the magnetic behavior; but rather increases dynamic viscosity, especially in the presence of the external magnetic field, which is considered as a stabilizing factor. Conclusion: Adding the white lithium grease as a stabilizer delays the sedimentation of the prepared sample by 1023%. The lowest sample in sedimentation rate has the highest viscosity, which satisfies 2.7% in 24 hours, but it shows a negative effect on the magneto-rheological properties, which leads to unstable viscosity readings due to MR fluid agglutination. Working temperature is a critical parameter that can affect the behavior of MR fluid; the viscosity of MR fluid under the effect of magnetic field is inversely proportional to the working temperature. Sample DELTA is the most promising for the application in automotive dampers which are used to decrease vehicle vibration. :

Design and Development of Magneto Rheological Dampers for Bicycle Suspensions

1999 ◽  
Author(s):  
Mehdi Ahmadian
Keyword(s):  
Dynamic Performance ◽  
Mr Damper ◽  
Test Results ◽  
Design And Development ◽  
Damping Force ◽  
Mr Fluid ◽  
Performance Improvements ◽  
Mr Dampers ◽  
Force Velocity ◽  
Magneto Rheological

Abstract The design and fabrication of a magneto rheological (MR) damper for bicycle suspension applications is addressed. Two 1998 Judy® Dampers are retrofitted with MR valves, to achieve the damping force adjustability that the MR fluid offers. One design attempts to use as many of the Judy® Damper components as possible. The second design significantly modifies the Judy® Damper, to better accommodate the MR valve and ease of fabrication and assembly, although fitting into the same envelope as the Judy® damper for a direct retrofit. The two MR dampers are fabricated and assembled for force-velocity characterization testing. The test results show that properly-designed MR dampers can provide significant dynamic performance improvements, as compared to conventional passive bicycle dampers.

Improving Vehicle Performance and Operator Ergonomics: Commercial Application of Smart Materials and Systems

2011 ◽  
Author(s):  
Douglas Ivers ◽  
Douglas LeRoy
Keyword(s):  
Smart Materials ◽  
Mr Damper ◽  
Electrical Current ◽  
Step Response ◽  
Commercial Application ◽  
Material Technology ◽  
Mr Fluid ◽  
Mr Dampers ◽  
Magneto Rheological ◽  
Scale Step

This paper will discuss how controllable material technology, such as the use of active magneto-rheological (MR) dampers, improves vehicle primary and secondary suspensions. Although relatively new to the marketplace, semi-active suspensions in commercial automobiles and off-highway vehicles have been proven through the use of active MR dampers since 1998. In fact, MR suspension dampers are found today on the commercial vehicles of an increasing number of automotive OEMs and leading off-highway OEMs. MR fluid dampers are simple in design and have the advantage of no moving parts. The resistive force from an MR damper is generated as iron particles, suspended in the magneto-rheological fluid (MR fluid); pass through a magnetic field controlled by the electrical current passing through an electric coil contained within a moving piston surrounded by fluid. By adjusting the current to the damper coil in response to feedback from vehicle sensors and a controller, the damping response of the suspension can be optimized and controlled in real time to provide optimal operator comfort. The MR Damper System has a full-scale step response of less than 10 milliseconds. Sophisticated control algorithms adapt to large changes in payload, enabling the vehicle to meet ride metrics without pneumatic load leveling. Other benefits of the MR damping system include higher speed in NATO double-lane change tests, reduced risk of roll-over, improved accuracy of mounted weapons, and improved vehicle durability and readiness.

Design and Performance Analysis on MR-Shock Absorber

2014 ◽  
Vol 984-985 ◽  
pp. 648-655
Author(s):  
M.L. Brabin Nivas ◽  
T. Prabaharan ◽  
J. Libin ◽  
T. Bibin Jose
Keyword(s):  
Magnetic Field ◽  
Mr Damper ◽  
Fast Response ◽  
Damping Force ◽  
Clear Fluid ◽  
Carrier Fluid ◽  
Fluid Turbulence ◽  
Mr Fluids ◽  
And Performance ◽  
Magneto Rheological

Abst r a c t -Magneto rheological aqueous is an old advancing to the bazaar at top speed. Excellent appearance like fast response, simple interface amid electrical ability ascribe and automated ability output, and absolute controllability accomplish MRF technology adorable for abounding applications.The aim of this project is preparation of MR-fluids by using the different types of carrier fluid mixed with iron powder and stability and magnetic properties are analysed. Thesedimentation of iron particles can be reduced by using additives. The sedimentation can be analysed by boundary variation of the clear fluid to the fluid turbulence. The viscosity of smart fluid can be increased by varying the applied magnetic field.The performance of the MR-damper depends on the applied maximum magnetic field and the hydraulic circuit design. The MR-damper force by increasing the magnetic field can be analysed by sing the FEMM V4 Software.Damping force depends on the excitation of current and magnetic field.Key words: Rheological, magnetic field, damping force, FEMM, flux density

Sign in / Sign up

Export Citation Format

Share Document