Search

Your search keyword '"Eguchi, Masato"' showing total 39 results
Start Over Author "Eguchi, Masato"
39 results on '"Eguchi, Masato"'

1. Crystal rotation and microstructures in an aluminum single-slip system under tensile loading

Author

Yoshida, Yutaka, Jun-ichi, Shibano, Ken-ichi, Fukuda, Terabayashi, Kengo, Eguchi, Masato, Kajiwara, Kentaro, Shobu, Takahisa, and Shiro, Ayumi

Abstract

単結晶のとの角度が引張荷重方向に対して45°である、アルミニウム単すべり系の(220)面の回転角度を実験的に調査した。SPring-8のBL28B2における放射光白色X線を利用し、とに沿ったいくつかのスポット（50×50μm）について結晶回転を調査した。負荷ひずみε=5%において、軸に沿った測定では垂直面の(220)面の結晶回転が、0.9mm～1.4mmの範囲で、0.850°～5.438°まで相対的に増加していた。さらに透過型電子顕微鏡を利用し、に沿った各スポットの転位セルや亜結晶粒のサイズを確かめた。この研究で明らかにされる基本的な局所結晶学は、材料の延性損傷を評価する方法として確立するために有効である。

Published
2018

2. Rotordynamic forces acting on three-bladed inducer under supersynchronous/synchronous rotating cavitation

Author

Yoshida, Yoshiki, Eguchi, Masato, Motomura, Taiichi, Uchiumi, Masaharu, Kure, Hirotaka, and Maruta, Yoshiyulki

Subjects
Mechanics -- Research, Cavitation -- Research, Force and energy -- Research, Turbomachines -- Mechanical properties, Turbomachines -- Acoustic properties, Engineering and manufacturing industries, Science and technology
Abstract

Asymmetric cavitation, in which cavity lengths are unequal on each blade, is known as a source of cavitation induced shaft vibration in turbomachinery. To investigate the relationship of the uneven cavity length and rotordynamic force in a cavitating inducer with three blades, we conducted two experiments. In one, the growth of cavity unevenness at the inception of synchronous rotating cavitation in cryogenic flow was observed, and in the other, the rotordynamic fluid forces in water were examined by using a rotordynamic test stand with active magnetic bearings. Rotordynamic performances were obtained within a wide range of cavitation numbers, and whirl/shaft speed ratios included supersynchronous/synchronous rotating cavitation. These experimental results indicate that the shaft vibration due to the rotating cavitation is one type of self-excited vibrations arising from the coupling of cavitation instability and rotordynamics. [DOI: 10.1115/1.3425727] Keywords: cavitating inducer, rotating cavitation, rotordynamic forces, self-excited vibration, tip clearance

Published
2010

7. Rotordynamic Fluid Forces of Floating Ring Seal for Rocket Turbopump

Author

Hiromatsu, Jun, Uchiumi, Masaharu, Takada, Satoshi, Nagao, Naoki, Eguchi, Masato, and Inoue, Hideyuki

Subjects
Floating ring seal, Whirling motion, Bulk-flow model, Stribeck curve, Rotordynamic forces
Abstract

A floating ring seal (FRS) has been employed as a noncontact type seal, which seals in high-pressure liquid oxygen for the rocket engine turbopump. The turbopump, high-speed, high-power turbomachinery, has suffered from rotor vibration problems up to the present time. However, as the dynamic behavior of FRS has rarely been focused on, it is necessary to clarify the rotordynamic (RD) fluid forces of FRS. The objectives of the present study were to evaluate the RD fluid forces of FRS analytically (bulk-flow model) and experimentally, and to elucidate the structural behavior of FRS caused by the whirling motion of the rotor. Evaluation of RD fluid forces was attempted, and development of a program for evaluation of the FRS is now in progress. RD fluid forces of FRS were measured by an experimental apparatus with an active magnetic bearing. These forces had no significant impact on rotordynamic stability. The axial force induced by differential pressure presses the floating-ring (FR, the component of the FRS) against the stationary housing. Because of the increasing friction force of the secondary contact surface, high axial loads increase the radial force required to reposition the FR. Therefore, it is very important to investigate rotordynamic forces as tribological behavior., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA0062043000, レポート番号: JAXA-RM-13-008E

Published
2013

8. JSEPA (Japan-Singapore Economic Partnership Agreement) and future trade policy

Author

Eguchi Masato

Subjects
Economic policy -- International aspects, Business, Business, international
Abstract

The Economic Partnership Agreement between Japan and Singapore is discussed. The implications of the agreement over the Japanese international trade policy are examined, including the acceptance of free trade and of bilateral trade agreements.

Published
2001

12. Rotordynamic Fluid Forces of Floating Ring Seal for Rocket Turbopump

Author

弘松, 純, 内海, 政春, 高田, 仁志, 長尾, 直樹, 江口, 真人, 井上, 秀行, Hiromatsu, Jun, Uchiumi, Masaharu, Takada, Satoshi, Nagao, Naoki, Eguchi, Masato, Inoue, Hideyuki, 弘松, 純, 内海, 政春, 高田, 仁志, 長尾, 直樹, 江口, 真人, 井上, 秀行, Hiromatsu, Jun, Uchiumi, Masaharu, Takada, Satoshi, Nagao, Naoki, Eguchi, Masato, and Inoue, Hideyuki

Abstract

A floating ring seal (FRS) has been employed as a noncontact type seal, which seals in high-pressure liquid oxygen for the rocket engine turbopump. The turbopump, high-speed, high-power turbomachinery, has suffered from rotor vibration problems up to the present time. However, as the dynamic behavior of FRS has rarely been focused on, it is necessary to clarify the rotordynamic (RD) fluid forces of FRS. The objectives of the present study were to evaluate the RD fluid forces of FRS analytically (bulk-flow model) and experimentally, and to elucidate the structural behavior of FRS caused by the whirling motion of the rotor. Evaluation of RD fluid forces was attempted, and development of a program for evaluation of the FRS is now in progress. RD fluid forces of FRS were measured by an experimental apparatus with an active magnetic bearing. These forces had no significant impact on rotordynamic stability. The axial force induced by differential pressure presses the floating-ring (FR, the component of the FRS) against the stationary housing. Because of the increasing friction force of the secondary contact surface, high axial loads increase the radial force required to reposition the FR. Therefore, it is very important to investigate rotordynamic forces as tribological behavior., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations

Published
2015

14. Effect of nitrogen-containing polymer wrapped around carbon nanotubes for Li–O2battery cathode

Author

Fujigaya, Tsuyohiko, Kanamori, Ryota, Hirata, Shinsuke, Morita, Junichi, Matsumoto, Masamichi, Eguchi, Masato, Jang, Il-Chan, Ishihara, Tatsumi, and Nakashima, Naotoshi

Abstract

In the development of lithium (Li)–oxygen (O2) rechargeable batteries, the improvement of the rechargeability is one of the key issues to be solved. Herein, a novel strategy to solve this issue is explored using polymer-wrapped single-walled carbon nanotubes (SWCNTs) as the cathode material. Poly[2,2’-(2,6-pyridine)-5,5’-bibenzimidazole] (PyPBI), employed as the wrapping polymer of the SWCNTs, served to coordinate Li ions and to facilitate a favorable deposition of the discharge products on the SWCNTs during the discharge reaction at the cell cathode. As a result, the rechargeability of the cell (SWCNT/PyPBI-cell) was improved compared to the cell having nonwrapped SWCNTs as the cathode (SWCNT-cell). Single-walled carbon nanotubes (SWCNTs) wrapped by poly[2,2’-(2,6-pyridine)-5,5’-bibenzimidazole] (PyPBI) was used for a cathode material of lithium (Li)-oxygen (O2) rechargeable battery. Compared to the Li–O2cell using nonwrapped SWCNTs, the cell using PyPBI-wrapped SWCNTs showed improved rechargeability during charge–discharge cycles. It was revealed that PyPBI layer facilitated the homogeneous deposition of the discharge products, resulting the smooth reaction during the cycles. The coordination of Li ion onto PyPBI surface might be the key mechanism to realize the homogeneous deposition.

Published
2019
Full Text
View/download PDF

17. Rotordynamic fluid forces acting on cavitating inducer in whirling motion

Author

Yoshida, Yoshiki, Eguchi, Masato, Motomura, Taiichi, Uchiumi, Masaharu, Kure, Hirotaka, and Maruta, Yoshiyuki

Subjects
Rotordynamic Fluid Force, Inducer, Rotating Cavitation, Instability
Abstract

To investigate the relationship of the uneven cavity length and rotordynamic force in a cavitating inducer with three blades, the rotordynamic fluid forces acting on cavitating and whirling inducer were examined by using a rotordynamic test stand with active magnetic bearings. Rotordynamic performances were obtained within a wide range of cavitation numbers (sigma) and whirl(omega)/shaft(Omega) speed ratios included super-synchronous/synchronous/sub-synchronous rotating cavitation. These experimental results indicate that the rotating cavitation strongly affects the fluid reaction forces. The fluid reaction forces act on the inducer as a destabilizing forces at a certan cavitation number and whirl/shaft speed ratio., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA0064454000, レポート番号: JAXA-RM-09-004

Published
2009

Catalog

Books, media, physical & digital resources
See catalog results