• Title, Summary, Keyword: Bingham model

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Manufacturing of MR Dampers and Estimation of the Bingham Model Parameters (MR 댐퍼의 제작과 Bingham 모델의 매개변수 추정)

  • Lee, Gun-Myung;Park, Mun-Soo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.6
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    • pp.82-87
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    • 2014
  • Small MR dampers with a simple structure were designed and manufactured. The Bingham model was used to represent the dynamic characteristics of the damper, and the parameters of the model were estimated from experimental data which were obtained by harmonic tests. The value of the estimated yield shear force remains positive when no electric current is applied, and it increases slowly with the current. The estimated viscous damping coefficient has a value close to zero when no electric current is applied, and it increases almost linearly with the current.

Bingham Properties and Damping Force Control of an ER Fluid under Squeeze Mode (압착모드하에서 ER유체의 빙햄특성 및 댐핑력 제어)

  • 홍성룡;최승복
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.11
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    • pp.37-45
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    • 2002
  • This paper presents the field-dependent Bingham characteristics and damping force control of an electro-rheological (ER) fluid under squeeze mode operation. The squeeze force of the ER fluid due to the imposed electric field is analyzed and an appropriate size of the disk-type electrode is devised. On the basis of the theoretical model of the ER fluid under squeeze mode operation, the yield stress and response speed of the ER fluid are distilled from the time responses of squeeze force to the step electric potentials. Measured squeeze forces under various excitation conditions are compared with the predicted ones from Bingham model and time constant obtained at the transient response test. In addition, the controllability of the field-dependent damping force of the ER fluid under squeeze mode is experimentally demonstrated by implementing simple PID controller.

Control Performance Investigation of MR Fluid Damper using Herschel-Bulkley Shear Model (Herschel-Bulkley 모델을 이용한 MR 댐퍼 승용차의 제어 성능 고찰)

  • 이덕영;황우석
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • pp.323-328
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    • 2002
  • The control performance of a vehicle installed with an MR(magnetorheological) fluid-based damper is investigated on the basis of Herschel-Bulkley shear model. Generally, most of MR fluid damper has been analyzed based on a simple Bingham-plastic shear model. However, the Bingham-plastic shear model can not well describe the behavior of the damper on the condition of high velocity and high current field input. Therefore, in this study, the Herschel-Bulkley shear model in which the constant post-yield plastic viscosity in Bingham model is replaced with a power law model dependent on shear rate is used to assess control performance of a vehicle with MR fluid damper suspension system. This study deals with a two-degree-of-freedom suspension using the MR fluid damper for a quarter car model. The response for the bump input to identify the fastness of MR fluid damper embedded skyhook controller and requested magnetic field are investigated.

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Performance Evaluation of MR Damper using Equivalent Linearization Technique (선형화 기법을 이용한 MR 감쇠기 성능평가)

  • Lee, Sang-Hyun;Min, Kyung-Won;Lee, Myoung-Kyu
    • Journal of the Earthquake Engineering Society of Korea
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    • v.9 no.2
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    • pp.1-6
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    • 2005
  • The purpose of this paper is to evaluate the performance of an MR fluid damper for seismic vibration control of a structure in terms of equivalent linear damping based on linearization technique and to experimentally verify the results from linearization technique by comparing them to those from system identification testing of a building structure with the MR damper. First, among various models for the MR damper, the equivalent damping is estimated for the Bingham model which is mathematically simple. Second, the transfer function of a building structure with the MR damper is obtained by performing shaking table tests and the damping matrices of the structure are constructed using the modal information obtained by the transfer function. It is observed that the damping mathematically estimated using linearization technique for the Bingham model matches well with the damping coefficient experimentally obtained by system identification.

Shear stress analysis of phosphorylated potato starch based electrorheological fluid

  • Hong, Cheng-Hai;Choi, Hyoung-Jin
    • Korea-Australia Rheology Journal
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    • v.19 no.4
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    • pp.221-225
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    • 2007
  • Electrorheological characteristics of a dispersed system of phosphorylated potato starch particles in silicone oil investigated via a rotational rheometer equipped with a high voltage generator is being reanalysized. Flow curves of these ER fluids both under several applied electric field strengths and with different degrees of phosphate substitution were mainly examined via three different rheological constitutive equations of Bingham model, De Kee-Turcotte model and our previously proposed CCJ model. Among these, the CCJ equation was found to fit the data of phosphorylated potato starch well.

The Flow Visualization of ER Fluid Between Two Parallel-Plate Electrodes Separated by Small Distance (좁은 평행평판전극 사이의 ER유체 유동의 가시화)

  • Park, Myeong-Kwan;Rhee, Eun-Jun;Oshima, Shuzo;Yamane, Ryuichiro
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.7
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    • pp.801-810
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    • 1999
  • The purpose of present research was to get characteristics and basic knowledges of electrorheological(ER) suspension. To observe behaviors of the ER suspensions. transparent conductive plates were used to visualize the flow of ER suspensions between two parallel plate electrodes. The influence of flowing speed and intensity of electric field on the ER fluid were examined in circle-shaped electric field, and it takes several hundred milliseconds that suspensions in flow cluster. The present study also conducts a numerical analysis adopting the Bingham model. It is found that simple Bingham model can not property describe the flow behavior in the parallel plates.

An Analysis of Debris Flow Movements Using Rheological Model (레올로지 모델을 이용한 토석류 이동해석)

  • 김상규;서흥석
    • Geotechnical Engineering
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    • v.13 no.5
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    • pp.133-144
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    • 1997
  • It was proved from the viscosity test for deposits of debris flows(Kim and Seo, 1997) that the property of debris flows could be represented as Bingham plastic model. Based on this bahavior, numerical analysis for the movement of debris flows is carried out by using a computer progran Polyflow which huts been developed for the analysis of the behavior of non-Newtonian fluid. The numerical results obtained from two sites agree well with the movement predicted by an empirical formula. It can be concluded, therefore. that this scheme can be used for the analysis of the movement of debris flow.

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Control Performance Evaluation of Shear Type Damper using SMG Fluid (SMG 유체를 이용한 전단형 댐퍼의 제어성능평가)

  • Heo, Gwang Hee;Jeon, Seung Gon;Seo, Sang Gu;Kim, Dae Hyeok
    • Journal of the Earthquake Engineering Society of Korea
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    • v.23 no.2
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    • pp.141-147
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    • 2019
  • This research focuses on developing the Smart material with Grease adopted as a base oil to overcome a particle deposition caused by the MR fluid consisting of a silicon, which maximizing the characteristics and advantage of the MR fluid. By adopting the SMG fluid to a shear damper, this paper aimed to evaluate the control performance of it according to the variation of intensity of electric current(0 A, 0.5 A, 1.0 A, 1.5 A, 2.0 A, 2.5 A) and frequency(0.5 Hz, 1 Hz, 2 Hz). Subsequently, the usability of the SMG damper was analyzed by comparing the dynamic model of it to that of the other types of dampers(Power(Involution) Model, Bingham Model). As a result, DR, the performance indicator of semi-active damper, shows approximately 5 in a condition of 2 Hz. Also while confirming the excellent performance like the Power and the Bingham model, it raises the possibility to exploit it as the semi-active damper.

Active Tension Control Using an ER Brake Actuator (ER브레이크 작동기를 이용한 능동 장력 제어)

  • Park, S.B.;Kim, G.W.;Cheong, C.C.
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.8
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    • pp.102-111
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    • 1996
  • This paper presents a proof-of-concept investigation on an active tension control using an ER (electro-rheological) brake actuator. Firstly, an ERF (electro-rheological fluid) which has an inherent reversible feature from Newtonian fluid to Bingham fluid upon applying an electric field is composed, and its property is tested to obtain intrinsic parameters of the Bingham model. An appropriate size of the ER brake is manufactured on the basis of the Bingham model, and dynamic characteristics of the brake are experimentally identified. After formulating a governing equation of motion of the tension control system, a sliding mode controller is designed to achieve a certain desired level of tension. Both simulation and experimental works are undertaken in order to demonstrate the efficiency and feasibility of the proposed active tension control method.

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Performance Evaluation of Small Dampers Using SMG Fluid (SMG 유체를 이용한 소형댐퍼의 성능평가)

  • Heo, Gwang Hee;Jeon, Seung Gon;Seo, Sang Gu;Kim, Dae Hyeok
    • Journal of the Earthquake Engineering Society of Korea
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    • v.23 no.4
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    • pp.211-219
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    • 2019
  • In this study, SMG(Smart Material with Grease) was developed, which was improved the precipitation minute particle in grease during long term standstill. Also, small-sized cylinder damper equipped with an electromagnet in a piston was developed for using a performance evaluation of the damper with SMG and the dynamic load test, and damping force using Power model and Bingham model was derived in order to compare to the result of that of the damper. The data obtained from the dynamic load test were analyzed and plotted, and then a dynamic range was calculated to evaluate the usability of the damper with SMG. The performance of the damper with SMG was compared to the damping forse derived from the Power and Bingham model. The result of this evaluation shown that the usability of SMG damper was demonstrated by this test as a semi-active controlling equipment of small-sized damper.