• Title/Summary/Keyword: fluid property

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Property of Multi-Direction Mount Using Magneto-Rheological Fluid (MR유체를 이용한 다방향 제진형 마운트의 응답특성)

  • Ahn, Young-Kong;Sin, Dong-Choon;Yag, Bo-Suk;Kim, Dong-Jo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.325.1-325
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    • 2002
  • This paper presents property of the squeeze mode type mount using Magneto-Rheological fluid (MR fluid). The mount can isolate multi-directional vibrations, and also effectively reduce the vibrations in a wide range of disturbance frequency by controling the applied magnetic field. The shape of the mount is the same that of squeeze film damper. In the present work, the performance of this mount was experimentally investigated according to changing the magnetic field strength. (omitted)

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Response Property of Multi-directional Mount Using Magneto-Rheological Fluid (MR유체를 이용한 다방향 제진형 마운트의 응답특성)

  • 안영공;신동춘;양보석;이일영;김동조
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.13 no.7
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    • pp.517-523
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    • 2003
  • This paper presents response property of the squeeze mode type mount using Magneto-Rheological fluid (MR fluid) . The MR mount for the isolation of multi-directional vibrations was constructed in this study. Both the mechanism and shape of the mount are the same as squeeze film dampers for a rotor system. In the present work, the performance of the mount was experimentally Investigated according to the magnetic field strength. The experimental results present that the MR mount can effectively reduce the vibration in a wide range of frequency by controlling the applied electromagnetic filed strength. Viscous damping and stiffness coefficients of the MR mount tend to be changed according to the variation of the applied currents In this study.

Equivalent Mechanical Property for Stress Analysis on Lined Pipe (Lined Pipe의 응력해석을 위한 등가 물성치 계산)

  • Choe, Jae-Seung;Jeong, Jin-Han
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.3
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    • pp.445-451
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    • 2002
  • The refractory-lined pipe is used to protect the system from high-temperature of the internal flow. The property of the refractory has an effect upon the stress analysis for fluid catalytic cracking(FCC) unit piping design. The equivalent elastic modulus and density considering steel and refractory must be applied in the stress analysis of the system. In the research, the theoretical method to obtain the value of the equivalent property is introduced and then the parametric analysis is carried out to understand the characteristic of the material properties, and the stress analysis is performed with reactor, the part of FCC unit.

Temperature-Dependent Hysteresis Investigation of Electro - Rheological Fluid Using Preisach Model (Preisach 모델을 이용한 ER 유체의 온도별 히스테리시스 특성 고찰)

  • 한영민;이호근;최승복;최형진
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.316-322
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    • 2002
  • This paper presents the temperature-dependent hysteresis identification of an electro-rheological (ER) fluid under various operating temperatures using the Preisach model. As a first step, polymethylaniline (PMA) particles are prepared and mixed with silicone oil to make an ER fluid. A couette type electroviscometer is then employed to obtain the field-dependent shear stress. In order to show the suitability of the Preisach model to predict a physical hysteresis phenomenon of the ER fluid, two significant properties; the minor loop property and the wiping-out property are experimentally examined under three dominant temperature conditions. Subsequently, the Preisach model fur the PMA-based ER fluid is identified using experimental first order descending (FOD) curves. The effectiveness of the identified hysteresis model is verified in the time domain by comparing the predicted field-dependent shear stress with the measured one under the both specified and unspecified temperatures. In addition, the hysteresis model proposed in this work is compared to Bingham model.

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Investigation on Temperature-dependent Hysteresis of Electro-rheological Fluid Using Preisach Model (Preisach 모델을 이용한 ER유체의 온도별 히스테리시스 특성 고찰)

  • 한영민;이호근;최승복;최형진
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.8
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    • pp.648-656
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    • 2002
  • This paper presents the identification of temperature-dependent hysteresis of an electro-rheological (ER) fluid under various operating temperatures using the Preisach model. As a first step, polymethylaniline (PMA) particles are prepared and mixed with silicone oil to make an ER fluid. A couette type electroviscometer is then employed to obtain the field-dependent shear stress. In order to show the suitability of the Preisach model to predict a physical hysteresis phenomenon of the ER fluid, two significant properties; the minor loop property and the wiping-out property are experimentally examined under three dominant temperature conditions. Subsequently, the Preisach model for the PMA-based ER fluid is identified using experimental multiple first order descending (FOD) curves. The effectiveness of the identified hysteresis model is verified in the time domain by comparing the predicted field-dependent shear stress with the measured one under the both specified and unspecified temperatures. In addition, the hysteresis model proposed in this work is compared to Bingham model.

A NOVEL MERHOO AND PROCEDURE FOR ON-LINE MEASUREMENT OF FLUID PROPERTIES FOR CONTROL AND OPTIMIZATION

  • Kaya, Azmi;Keyes, Marion-A.
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.844-847
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    • 1989
  • This work describes an on-line method and procedure for calculating the fluid properties in real time while system is in operation. The method utilizes function blocks of distributed control systems. Thermodynamic relations of fluid from tables along with a fluid property formula are imbedded into the proposed signal processing block. Once the pressure and temperature measurements are entered the system provides other properties.

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The Analysis of Hydrological Property with Curved-channel Type (하도만곡형상에 따른 수리특성분석)

  • Ahn, Seung-Seop;Lee, Sang-Il;Park, Dong-Il;Kim, Wi-Seok
    • Journal of Environmental Science International
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    • v.20 no.10
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    • pp.1309-1317
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    • 2011
  • This study selected 6 river reach, which have various curved-channel, included in an object of study as making the Nakdong River, which is a real nature river, as a point of an object of study by using SMS RMA-2 model, a 2D numerical analysis model, and applied project flood and analyzed and examined characteristic of hydrological property and super-elevation, which includes characteristic of the velocity of a moving fluid. As a result, in a river reach, whose width is wide, angle of curved-channel has impact on the velocity of a moving fluid of inside of curved-channel and in a river reach, whose width is narrow, the radius of curvature and width of the river have impact on the velocity of a moving fluid of inside of curved-channel. Also it found out that the ratio of reduction in water-level of inside of curved-channel is more bigger than ratio of increasing in water-level of outside of curved-channel when project flood is increasing and angle of curve is increasing. Based on this, this study would be used as a expectation of danger and preliminary data in planning real river or a business, that creates an environment.

Research on the Characteristics of Water inside a Human's Body and its Metabolism (인체내 수액의 특성 및 대사기전에 대한 연구 -진액.혈.한.소변.정의 생성기전 및 성질에 대하여-)

  • 백상용
    • The Journal of Korean Medicine
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    • v.24 no.3
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    • pp.130-137
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    • 2003
  • Water, in a living being, is as essential as the essence derived from food is in maintaining one's life. The concepts are expressed in forms of "food and drink" and "drink-food" in the ${\mathbb{\ulcorner}}Hwangjenakyoung{\mathbb{\lrcorner}}$ and most of the other oriental medicine related references. Following the steps of the human body's metabolism, the water source builds up characteristic formations, such as bodily fluids (blood/perspiration/urine/essence), in each transforming phase according to the nature of the Ki that propels the transformation. Furthermore, each characteristic formations has its' own suitable duties, distinctive features and its field of activation. The vital energy of life is identified as a positive property due its fluidity and its formless nature. In order for this vital energy to come into its own, it needs to weld into one with the material-natured body of the negative property which will embrace the positive property and transform it into body fluid. Water taken into a body will undergo the first activation of Ki, dissolving the Wigi and the Wongi and transforming into the primary body fluid. The delicates among the dissolved Ki will once again go through a transformation in the Jungcho. It will turn into red blood, with influence of the vital function. When the vital energy completes its duties in all parts of the body, it combines with water again and transforms into the secondary bodily fluid. This is when the Takgi gets filtered and the new enriched essence is created.

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Theoretical Analysis of Lined Pipe (Lined Pipe 이론 해석)

  • Jung, Jin-Han;Choi, Jae-Seung
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.964-968
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    • 2001
  • The refractory-lined pipe is used to protect the system from high-temperature of the internal flow. The property of the refractory has an effect upon the stress analysis for fluid catalyst cracking(FCC) unit piping design. The equivalent elastic modulus and density considering steel and refractory must be applied in the stress analysis of the system. In the research, the theoretical method to obtain the value of the equivalent property is introduced and then the parametric analysis is carried out to understand the characteristic of the material properties.

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Study on the Compact MR fluid Brake for the Training and Sporting Equipment for Leg Rehabilitation (하지 재활운동치료 기구에 적용하기 위한 소형 MR 유체 브레이크에 관한 연구)

  • Park, Woo-Cheul;Lee, Hyun-Chang;Kim, Il-Gyoum
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.7
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    • pp.2878-2885
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    • 2012
  • In this study, the training and sporting equipment for leg rehabilitation featuring the MR fluids is proposed. The compact MR fluid brake is designed and manufactured to apply to the rehabilitation training and sporting mechanism. The resistance characteristic of the MR fluid brake is controllable by varying the magnetic field around the fluid. Under consideration of spatial limitation, design parameters which are related with the magnetic strength are determined to maximize to a torque using finite element method. The FE analysis is performed using a commercial code, ANSYS Workbench. The proposed brake device is manufactured, and its field-dependant torque is experimentally evaluated. When the electric current is supplied, the torque of the MR fluid brake is increased and the response is very fast. Depending on the strength of the current supply, torques of the MR fluid brake also increase similar to Bingham property of MR fluid.