Presentations -

Cluster formation in two dimensional channel flow of a magnetic fluid under uniform magnetic field

Akihiro Nakamura, Satoshi Suzuoka and Tatsuo Sawada

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

2011.09

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Poster presentation

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When magnetic field is applied to a magnetic fluid, ferromagnetic particles aggregate along magnetic force lines and form clusters. These clusters form chain clusters in applying magnetic field after a long time. We make clear the influence of chain clusters on velocity field in two dimensional channel flow under a uniform magnetic field.

Effect of uniform magnetic field on magnetorheological fluid under impact load

Yoshitaka Moroka, Ahmad Isnikurniawan, Hiromichi Ohba and Tatsuo Sawada

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

2011.09

, 

Poster presentation

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A simple U-tube filled with the orifice was used. The resisting force acting on a MR fluid was investigated and the influence of applied magnetic fields on velocities and accelerations of the piston which produced the impact load.

Experimental investigation on the effect of magnetic field on magnetorheological fluids under an impact load

Ahmad Isnikurniawan, Yoshitaka Moroka, Hiromichi Ohba and Tatsuo Sawada

The 7th Japanese-Mediterranean Workshop on Applied Electromagnetic Engineering for Magnetic, Superconducting and Nano Materials (Budapest) , 

2011.07

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Poster presentation

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MR流体を用いた衝撃緩衝器に関する基礎的な実験を行った。荷重や印加磁場変化の緩衝性能におよぼす影響を調べた。

Effect of Magnetic Field on Forced Convective Heat Transfer in Rectangular Duct Flow of a Magnetic Fluid

Masaaki Motozawa, Jia Changa, Tatsuo Sawada and Haruo Kawaguchi

The 48th National Heat Transfer Symposium of Japan (Okayama) , 

2011.06

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Oral presentation (general), Heat Transfer Society of Japan

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磁性流体矩形管流れの強制対流熱伝達特性において，局所熱伝達率の磁場印加による影響を調べた。さらに，超音波を用いた流速分布計(UVP)により，印加磁場下の磁性流体の流速分布も測定した。その結果，層流域では，磁場印加領域において局所熱伝達率が増加しており，伝熱壁に対する速度勾配も増加していた。

Behavior of MR fluid under a uniform magnetic field subjected to an impact load

Ahmad Isnikurniawan, Hiromichi Ohba, Yoshitaka Moroka and Tatsuo Sawada

The 23th Symposium on Electromagnetics and Dynamics (Nagoya) , 

2011.05

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Oral presentation (general), Japan Society of Applied Electromagnetics and Mechanics

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Qualitative analysis of the MR fluid behavior under impact load is proposed. The MR fluid placed on the U-tube was subjected to an impact load through a piston rod. The experiment was conducted by measuring the displacement, velocity and acceleration of the piston rod, subjected to impact load on the MR fluid. The discussion on the influence of the peak acceleration of the piston rod and the peak value of the impact force is presented.

Influence of Applying Magnetic Field on Velocity Field in Two Dimensional Channel Flow of Magnetic Fluid

Akihiro Nakamura, Satoshi Suzuoka and Tatsuo Sawada

The 23th Symposium on Electromagnetics and Dynamics (Nagoya) , 

2011.05

, 

Oral presentation (general), Japan Society of Applied Electromagnetics and Mechanics

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Internal particles of magnetic fluid form chain cluster by applying magnetic field for a long time. Influence of chain cluster formation on velocity field of two dimensional channel flow was investigated experimentally.

Experimental measurements of ultrasonic propagation attenuation in MR fluids under a uniform magnetic field

Ahmad Isnikurniawan, Jun Kuroiwa, Yuta Suzuki and Tatsuo Sawada

日本機械学会関東支部第17期総会講演会 (Yokohama) , 

2011.03

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Oral presentation (general), JSME

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MR流体中を伝播する2MHzの超音波の減衰率に関する実験的検討を行った。

Experimental study of pressure variation due to sloshing in a rectangular tank

Jean Klingler, Shunsuke Kaneko and Tatsuo Sawada

日本機械学会関東支部第17期総会講演会 (Yokohama) , 

2011.03

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Oral presentation (general), JSME

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複数の小型圧力センサを用いて、スロッシング共振点付近で振動する矩形容器内の流体圧力を測定し、出力信号のフーリエ解析を行った。加振振幅・加振振動数をパラメータとして、測定位置毎に振幅・位相分布を調べた。

The relationship between magnetic field and change in natural sloshing frequency of magnetic fluid

Hayato Suzuki, Ken-ichi Ohno and Tatsuo Sawada

19th MAGDA Conference in Sapporo (Sapporo) , 

2010.11

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Poster presentation, The Japan Society of Applied Electromagnetics and Mechanics

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The frequency response of a tuned liquid damper with a magnetic fluid (Tuned Magnetic Fluid Damper, TMFD) is investigated experimentally. The relationship between the natural sloshing frequency of magnetic fluid and radial element of magnetic field has already been reported. We studied the natural sloshing frequency by changing the size of electromagnets, and ensure that a proposed theory is practical with any electromagnet.

Influence of Uniform Magnetic Field on Heat Transfer in Rectangular Duct Flow of a Magnetic Fluid

Masaaki Motozawa, Jia Chang, Tatsuo Sawada, Yasuo Kawaguchi

JSME Fluids Engineering Conference 2010 (Yonezawa) , 

2010.10

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Oral presentation (general), JSME

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磁性流体の矩形管内流れにおける印加磁場下の熱伝達特性を計測した。層流下での磁性流体の流れでは，磁場印加領域で局所的に熱伝達率は増加し，磁場が大きいほどその熱伝達率も大きくなることが分かった。

Ultrasonic Wave Propagation in MR fluids

Tatsuo Sawada and Muhammad Agung Bramantya

JSME Mechanical Engineering Congress, 2010 Japan(MECJ-10) (Nagoya) , 

2010.09

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Oral presentation (invited, special), JSME

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招待講演。ワークショップにおいて，MR流体内の超音波伝播特性について概説を行った。

The influence of magnetic field swept rate on the ultrasonic propagation velocity of magnetorheological fluids

Muhammad Agung Bramantya and Tatsuo Sawada

The 12th International Conference on Magnetic Fluids (Sendai) , 

2010.08

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Oral presentation (general), The Magnetic Fluid Association of Japan

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印加磁場増加率を変化させた時，MR流体中を伝播する超音波伝播速度がどのように変化するかを，実験的に調べた。その結果，磁性体微粒子の沈殿効果が印加磁場強度に応じて変化することが明らかになった。

Study of ultrasonic wave propagation on magnetorheological fluid with different frequency

Muhammad Agung Bramantya, Jun Kuroiwa and Tatsuo Sawada

5th Pacific Rim Conference on Rheology (Sapporo) , 

2010.08

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Poster presentation, The Society of Rheology, Japan/Japanese Society of Biorheology, Hokkaido University/The Japan Society of Polymer Processing

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印加磁場増加率を変化させた時，MR流体中を伝播する超音波伝播速度が，超音波の周波数によってどのように変化するかを，実験的に調べた。

Analysis of a liquid sloshing of a tuned magnetic fluid damper for single and co-axial cylindrical containers

Ken-ichi Ohno, Hayato Suzuki and Tatsuo Sawada

The 12th International Conference on Magnetic Fluids (Sendai) , 

2010.08

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Poster presentation, The Magnetic Fluid Association of Japan

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単一円筒容器および同軸二重円筒を用いた同調磁性流体ダンパーにおいて，半径方向磁場分布を考慮した理論解析を行った。そして，その結果を実験結果と比較検討し，解析結果の妥当性を確認した。

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

Masaaki Motozawa, Jia Chang, Tatsuo Sawada, Yasuo Kawaguchi

The 12th International Conference on Magnetic Fluids (Sendai) , 

2010.08

, 

Poster presentation, The Magnetic Fluid Association of Japan

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長方形ダクト内の磁性流体流れの熱伝達特性におよぼす印加磁場の影響を調べた。その結果，熱伝達特性の顕著な向上を確認することができた。

Improvement of sloshing analysis for magnetic fluid

Ken-ichi Ohno, Hayato Suzuki and Tatsuo Sawada

The 6th Asia-Pacific Symposium on Applied Electromagnetics and Mechanics (Kuala Lumpur) , 

2010.07

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Poster presentation, Universiti Putra Malaysia

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磁性流体の円筒容器内スロッシングにおいて，半径方向磁場分布を考慮した新たな解析を行い，磁場形態による共振周波数変化に関する検討を行った。また，実験も行い，理論解析結果との比較検討を行った。

A study on the inner structure of magnetorheological fluids by image processing

Muhammad Agung Bramantya, Hiroki Takuma, Jun Kuroiwa and Tatsuo Sawada

The 6th Asia-Pacific Symposium on Applied Electromagnetics and Mechanics (Kuala Lumpur) , 

2010.07

, 

Poster presentation, Universiti Putra Malaysia

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MR流体に磁場を印加した場合のクラスター形成過程を顕微鏡で撮影し，画像処置を行い，クラスター個数を求めた。クラスタ個数の変化率を求め，印加磁場強度との関連を調べた。

Study of the inner structure of magnetorheological fluids by image processing

Muhammad Agung Bramantya, Hiroki Takuma, Jun Kuroiwa and Tatsuo Sawada

The 22th Symposium on Electromagnetics and Dynamics (Moji) , 

2010.05

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Oral presentation (general), JSME

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Magnetorheological (MR) fluids are kinds of typical functional fluids which changes its rheological properties when external magnetic field is applied. This study will elaborate inner structure of MR fluids by visualization method. It seems that the clustering structure more robust and dense when the magnetic field is increases.

Sloshing Analysis of Magnetic Fluid in Cylindrical Container under Axisymmetrical Magnetic Field

Ken-ichi Ohno, Hayato Suzuki and Tatsuo Sawada

The 22th Symposium on Electromagnetics and Dynamics (Moji) , 

2010.05

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Oral presentation (general), JSME

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任意容器内の磁性流体に直流磁場を加えた時スロッシング固有振動数は変化する。本研究では重力方向磁場だけではなく水平方向磁場のスロッシング固有振動数への影響を円筒容器を用いて調べた。

Magnetic field swept rate on the ultrasonic propagation velocity of magnetorheological fluids

Muhammad Agung Bramantya, Hiroki Takuma, Jun Kuroiwa and Tatsuo Sawada

Japanese Symposium on Magnetic Fluids (Yokohama) , 

2009.12

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

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磁場印加によるMR流体中を伝播する音速のスイープ・レートを実験的に調べた。