Presentations -

Influence of magnetic fields on natural frequency of a tuned liquid column damper with a magnetic fluid

Toshiyuki Oyamada, Hideaki Masuda, Kazuki IKari and Tatsuo Sawada

JSME Fluids Engineering Conference 2012 (Kyoto) , 

2012.11

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Oral presentation (general), JSME

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従来のTLCDの制振性能を改善するため, 定常磁場を印加することで固有振動数を制御可能としたセミアクティブ型液柱管ダンパーを製作し, 磁場による液柱固有振動数の変化について実験的解析を行った。

Characteristic velocity distribution of rectangular duct flow of a magnetic fluid under magnetic field

Masaaki Motozawa, Tsukasa Sekine, Tatsuo Sawada and Yasuo Kawaguchi

8th International Symposium on Ultrasonic Doppler Methods for Fluid Mechanics and Fluid Engineering (Dresden) , 

2012.09

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Oral presentation (general), Helmholtz-Zentrum Dresden-Rossendorf

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We measured the velocity distribution of a rectangular duct flow of a magnetic fluid using UVP. The experiments were carried out with changing external magnetic field intensity and Reynolds number of the magnetic fluid flow. On the basis of the results of these experiments, the influence of magnetic field on the velocity distribution of rectangular duct flow of magnetic fluid was discussed.

Experimental investigation of resistance force of MR fluid subjected to a shock loading

Ahmad Isnikurniawan, Hiromichi Ohba, Hiro Kaneko and Tatsuo Sawada

The 7th Asia-Pacific Symposium on Applied Electromagnetics and Mechanics (Ho Chi Minh City) , 

2012.07

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Oral presentation (general), Ho Chi Minh City University of Technology

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We proposed qualitative analysis to investigate resistance force of MR fluid when subjected to a shock loading. The MR fluid was subjected to a shock loading through a piston rod which placed in the one side of the U-pipe. Experiments have been conducted by measuring displacement of piston rod and a resistance force. Based on the experimental result, the effect of orifice inner diameter on the resistance force of MR fluid was discussed.

Velocity Distribution Measurement of Rectangular Duct Flow of a Magnetic Fluid by UVP

Masaaki Motozawa, Tsukasa Sekine, Tatsuo Sawada and Haruo Kawaguchi

第40回可視化情報シンポジウム (Tokyo) , 

2012.07

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Oral presentation (general), The Visualization Society of Japan

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矩形管内を流れる磁性流体の速度分布を超音波を利用して計測し，速度分布および伝熱特性におよぼす磁場の影響を調べた。

Variation of forced convective heat transfer of rectangular duct flow of a magnetic fluid under magnetic field

Masaaki Motozawa, Tsukasa Sekine, Tatsuo Sawada and Yasuo Kawaguchi

13th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (Ankara) , 

2012.07

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Oral presentation (general), Gazi University

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矩形流路内を流れる磁性流体の強制対流熱伝達特性について，乱流と層流の場合での検討を行った。

Effect of a magnetic field on sloshing pressure in a magnetic fluid

Shunsuke Kaneko, Takayoshi Ishiyama and Tatsuo Sawada

13th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (Ankara) , 

2012.07

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Poster presentation, Gazi University

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Dynamic pressure response in an oscillating rectangular container filled with a magnetic fluid under a horizontal magnetic field was discussed. An investigation was made experimental approach based on the measurement of pressure at several points by pressure transducers and the real-time computation of a discrete Fourier transform.

Investigation of cluster growth in MR fluids using an ultrasonic wave propagation

Ahmad Isnikurniawan, Jun Kuroiwa, Shunnosuke Abell and Tatstuo Sawada

13th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (Ankara) , 

2012.07

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Poster presentation, Gazi University

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We carried out experiments by applying different magnetic field (M/F) sweep rates to MR fluid. The ultrasonic propagation velocity was measured and the change of ultrasonic propagation velocity was calculated for various M/F sweep rate. The relation between the change of ultrasonic propagation velocity and M/F sweep rate was discussed.

Experimental study on damping characteristics of the tuned liquid column damper with a magnetic fluid

Hideaki Masuda, Toshiyuki Oyamada and Tatsuo Sawada

13th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (Ankara) , 

2012.07

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Poster presentation, Gazi University

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We designed a novel semi-active damper using a magnetic fluid as a working fluid of the tuned liquid column damper (MF-TLCD). Experiments were performed to analyze the effect of a magnetic field on natural frequencies of the MF-TLCD. Based on the experimental results, relations among setting positions of an electromagnet, strength of magnetic field, and changes of a natural frequency were discussed.

Experimental Investigation of Forced Convective Heat Transfer in Rectangular Duct Flow of a Magnetic Fluid under Magnetic Field

Masaaki Motozawa, Tsukasa Sekine, Tatsuo Sawada and Haruo Kawaguchi

The 49th National Heat Transfer Symposium of Japan (Toyama) , 

2012.06

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Oral presentation (general), Heat Transfer Society of Japan

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Effect of magnetic field on forced convective heat transfer in rectangular duct flow of a magnetic fluid was investigated experimentally. When the magnetic field is applied to the magnetic fluid laminar flow, heat transfer coefficient locally increased in the region where the magnetic field exists. The flow velocity at the center of the rectangular duct decreases and the velocity gradient in the near-wall region increased with increasing magnetic field intensity.

Experimental analysis of cluster growth in MR fluid under magnetic field

Ahmad Isnikurniawan, Jun Kuroiwa, Shunnosuke Abell and Tatsuo Sawada

The 24th Symposium on Electromagnetics and Dynamics (Totyama) , 

2012.05

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Oral presentation (general), The Institute of Electrical Engineers of Japan

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This paper presents experimental analysis of cluster growth in Magneto-rheological (MR) fluid. The experiments were conducted by applying magnetic field to MR fluid in different sweep rates. Magnetic field was swept from 0 to 400 mT at different time. Ultrasonic propagation velocity was measured and the change of ultrasonic propagation velocity was calculated. Based on the experiment result, the relation between the change of ultrasonic propagation velocity and M/F sweep rate is discussed. Furthermore, the relation between the maximum change of ultrasonic propagation velocity and various M/F sweep rate is presented.

Study on the Semi-activated Tuned Liquid Column Damper(TLCD) by using Magnetic Fluid

Toshiyuki Oyamada, Hideaki Masuda and Tatsuo Sawada

日本機械学会関東学生会第51回学生員卒業研究発表講演会, 

2012.03

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Oral presentation (general), 日本機械学会関東支部学生会

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同調液柱管ダンパー(TLCD)の作動流体として磁性流体を用い，電磁石によって外部から定常磁場を印加することで制振のセミアクティブ化を試みた。実験では液柱のみの1自由度強制振動実験と，液柱と構造物からなる2自由度強制振動実験を行い，磁場印加によって構造物振幅や圧力変動の周波数応答がどのように変化するかを調べた。

Damping characteristic of MR fluid under shock loading

Ahmad Isnikurniawan, Yoshikata Moroka，Hiromichi Ohba, Hiro Kaneko and Tatsuo Sawada

Japanese Symposium on Magnetic Fluids (Hikone) , 

2011.12

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Oral presentation (general), 磁性流体研究連絡会

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MR流体に衝撃力が加わった時の減衰特性が磁場によってどのように変化するかを調べた。

磁性流体を用いた液柱管ダンパーの制振特性

増田英晃, 小山田稔幸, 澤田達男

Japanese Symposium on Magnetic Fluids (Hikone) , 

2011.12

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Oral presentation (general), 磁性流体研究連絡会

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磁性流体を作動流体に用いることで磁場制御を可能にした液柱管ダンパーの提案とその振動特性におよぼす磁場の影響を調べた。

Ultrasonic propagation attenuation in an MR fluid under an external Magnetic ield

Ahmad Isnikurniawan, Jun Kuroiwa, Shunnosuke Abell and Tatsuo Sawada

The 20th MAGDA Conference in Pacific Asia (Kaohsiung) , 

2011.11

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Oral presentation (general), Japan Society of Applied Electromagnetics and Mechanics/National Kaohsiung First University of Science and Technology/Bureau of Foreign Trade

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Experiments were performed to measure how the ultrasonic propagation attenuation in an MR fluid under an external magnetic field was affected by temperature, elapsed time, magnetic field intensity, magnetic field angle, removal of the magnetic field, and hysteresis. The influence of the clustering structures on change of ultrasonic propagation attenuation in MR fluids is discussed.

Effect of the orifice inner-diameter on damping characteristic of MR fluid under shock loading

Hiromichi Ohba, Ahmad Isnikurniawan, Yoshitaka Moroka, Hiro Kaneko and Tatsuo Sawada

The 20th MAGDA Conference in Pacific Asia (Kaohsiung) , 

2011.11

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Oral presentation (general), Japan Society of Applied Electromagnetics and Mechanics/National Kaohsiung First University of Science and Technology/Bureau of Foreign Trade

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We propose a qualitative analysis to investigate the damping characteristic of the MR fluid under a shock loading. The experimental apparatus consists of a drop-test tower, U-pipe and sensor tower. MR fluid is placed in U-pipe which was subjected to the shock loading through a piston. The experiment was carried out by measuring the displacement, velocity and acceleration of piston. The effect of the orifice inner-diameter on damping characteristic of an MR fluid was discussed.

Effect of magnetic field on pressure drop in two-dimensional magnetic fluid flow

Akihiro Nakamura, Yasuhiro Fujita and Tatsuo Sawada

The 20th MAGDA Conference in Pacific Asia (Kaohsiung) , 

2011.11

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Oral presentation (general), Japan Society of Applied Electromagnetics and Mechanics/National Kaohsiung First University of Science and Technology/Bureau of Foreign Trade

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Effect of cluster formations on two-dimensional channel flow of a magnetic fluid flow was investigated. Pressure drop was measured by changing the application times of the magnetic field, Reynolds numbers and magnetic field intensities.

Dynamic pressure change of a magnetic fluid in a lateral oscillating container

Shunsuke Kaneko, Jean Klingler, Takayoshi Ishiyama and Tatsuo Sawada

The 20th MAGDA Conference in Pacific Asia (Kaohsiung) , 

2011.11

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Oral presentation (general), Japan Society of Applied Electromagnetics and Mechanics/National Kaohsiung First University of Science and Technology/Bureau of Foreign Trade

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Dynamic pressure change of a magnetic fluid in a lateral oscillating container was investigated. An experimental approach based on the measurement of pressure at several points by small disc-type pressure transducers was used. Several frequency response spectra are received. These results indicated that the free surface disturbance caused by the sloshing was suppressed by the applied magnetic field.

Effect of magntic field on forced convective heat transfer in rectangular duct flow of a magnetic fluid

Masaaki Motozawa, Jia Chang, Tatsuo Sawada and Yasuo Kawaguchi

The 22nd International Symposium on Transport Phenomena (Delft) , 

2011.11

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Oral presentation (general), Delft University of Technology

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Experiments have been performed with a closed-circuit loop with the rectangular duct having square cross-section for the test section. In case of laminar flow, when the magnetic field is applied to magnetic fluid, heat transfer was drastically enhanced locally in the region where the magnetic field exists. This heat transfer becomes large with increasing magnetic field and is saturated with applying more than 400 mT of magnetic field. In addition, velocity distribution of magnetic fluid flow also changed under magnetic field. On the contrary, in the case of turbulent flow, local heat transfer coefficient ratio does not increase but slightly decreases. This is because turbulent diffusion is largely suppressed by the magnetic field.

Effect of magnetic field on the ultrasonic propagation attenuation in MR fluids

Ahmad Isnikurniawan, Jun Kuroiwa and Tatsuo Sawada

VSJ Meeting (Toyama) , 

2011.09

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Oral presentation (general), The Visualization Society of Japan

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MR流体中を伝播する超音波の減衰特性を実験的に調べ，温度・磁場強度のおよぼす影響の検討を行った。

Experimental investigation on heat transfer characteristics in rectangular duct flow of a magnetic fluid under magnetic field

Masaaki Motozawa, Jia Chang, Tatsuo Sawada, Yasuo Kawaguchi

The 15th International Symposium on Applied Electromagnetics and Mechanics (Napoli) , 

2011.09

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Oral presentation (general)

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Heat transfer characteristics in rectangular duct flow of a magnetic fluid under magnetic field were investigated experimentally. As a result of this experiment, in laminar flow, when the magnetic field is applied to magnetic fluid, heat transfer coefficient drastically increases locally in the region where the magnetic field exists. On the contrary, in the turbulent flow, heat transfer is not enhanced but slightly decreases.