著者

中川 慶子 野々下 知泰 高橋 浩爾

出版者

社団法人 日本フルードパワーシステム学会

雑誌

油圧と空気圧 (ISSN:02866900)

巻号頁・発行日

vol.25, no.3, pp.425-432, 1994-05-15 (Released:2011-03-03)

参考文献数

8

被引用文献数

1 1

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In the pipeline of a hydraulic system or a liquid transportation system, liquid column separation occurs when the pressure drops below the gas release pressure or saturated vapor pressure. When the cavity produced by the column separation collapses, an extraordinary high build-up of pressure, which is very harmful for the hydraulic system and the components, can occur. The behavior of the dissolved air contained in the liquid makes this even more complicated. To predict the duration of the separation and the peak pressure caused by the collapse, a simple one-dimensional model is proposed, in which gas-liquid surfaces are taken and the effect of released air is taken into account using a homogeneous mixture approximation and the method of characteristics. With regards to the first pressure peak, the calculated results agree well with the experimental ones.

著者

瀬古 章雄 武藤 高義 山田 宏尚 田中 克典

出版者

社団法人 日本フルードパワーシステム学会

雑誌

日本油空圧学会論文集 (ISSN:13434616)

巻号頁・発行日

vol.30, no.2, pp.42-47, 1999

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The purpose of this study is to improve the facilities of BDSP into a more convenient one. As regards the first improvement, we have introduced a high-speed calculation method with a fluid line algorithm using a recursive formula. The recursive formula was derived analytically from each of the modal approximation models of the fluid rigid lines and fluid viscoelastic lines. As regards the second improvement, we have introduced a method for simulating the dynamic responses at the arbitrary position of the fluid line, in stead of the conventional method that allows calculation only at both ends of the fluid line. It could be verified in this study that simulation could be done much faster compared with the conventional ones, without any decrease in accuracy. Consequently, BDSP may be concluded to be a convenient and accurate tool for carrying out hydraulic system simulations.

著者

瀬古 章雄 武藤 高義 山田 宏尚

出版者

社団法人 日本フルードパワーシステム学会

雑誌

油圧と空気圧 (ISSN:02866900)

巻号頁・発行日

vol.27, no.2, pp.307-314, 1996

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In this study, a simulation program for hydraulic control systems has been developed. By using this program, the operator is capable of simulating the dynamic performance of systems without the need of any special knowledge as regards software or control engineering. The program was developed for use on personal computers that are most commonly used today. The simulation is carried out according to each operation in a very simple manner based on the block diagram representation of the systems. For these procedures, a graphical user inter-face was successfully incorporated into the program. Regarding the main features or functions of the program, it is possible to simulate pipeline elements, various kinds of nonlinear elements and even discrete time control systems.

著者

鈴木 勝正

出版者

社団法人 日本フルードパワーシステム学会

雑誌

油圧と空気圧 (ISSN:02866900)

巻号頁・発行日

vol.13, no.6, pp.417-425, 1982 (Released:2010-10-21)

参考文献数

6

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Oil hammer generates for an instant much greater pressure than that supplied to the pipe line, and this is important, indeed, in terms of the safety of oil hydraulic equipments. If you can take advantage of this phenomenon to pick up only the high pressure for a very short period of time, you will be able to make such a hydraulic pressure intensifier as can convert the oil pressure, produced by a low pressure pump, into several times higher one. In the case of water, a hydraulic ram utilizing this idea by means of waterhammer has been long investigated. However, its discharge pressure is several tenths MPa at most. For the oil hydraulics, to the author's knowledge, no report is available on an intensifier by means of oil hammer. Then, you would need a quite different structure because about one hundred times higher pressure will usually be needed. In the present research, an intensifier on a new principle was developed with a view to convert an oil pressure of several MPa into several times higher one and, moreover, to make more easily than a traditional intensifier consisting of oil cylinders. The discharge volume of the intensifier and the pressure fluctuation in the pipe line are theoretically predictable with a good accuracy.