著者

白石 直 渡壁 壽人 佐郷 ひろみ 中村 友道 石谷 嘉英 此村 守 山口 彰 藤井 正

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集 : JSME annual meeting

巻号頁・発行日

vol.2004, no.7, pp.103-104, 2004-09-04

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A flow-induced vibration test facility that simulates a hot leg piping of the Japanese sodium-cooled fast reactor (JSFR) with 1/3 scale is used to investigate the flow pattern and pressure fluctuations of the pipe. As the observation of flow pattern, the velocity distributions measured by LDV show the flow pattern is independent of Reynolds number at high Reynolds number. The maximum velocity is about 15 times the mean velocity in the elbow. A statistical analysis of the pressure fluctuations in a separation region shows the power spectrum is of white noise up to 20Hz, the autocorrelation sharply drops to zero less than 1 sec of time interval and the probability density distribution figures almost the Gaussian distribution, excepting its flatness-3 is 3.

著者

藤井 正 西口 洋平 此村 守 佐郷 ひろみ 白石 直 渡壁 壽人 中村 友道 石谷 嘉英

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集 : JSME annual meeting

巻号頁・発行日

vol.2004, no.3, pp.247-248, 2004-09-04

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A conceptual design study of the sodium-cooled fast reactor (JSFR) is in progress in "Feasibility Study on Commercialized Fast Reactor Cycle Systems". The cooling system of the reactor is composed of two loops in order to reduce plant construction cost. According to reduction of loop number, large diameter pipings are adopted in the primary cooling system, and the average sodium velocity in the piping increases to 9 m/s level. One of issues for piping design is to confirm hydraulic and flow-induced vibration behaviors of the piping under high Reynolds number (10^7 order level) conditions. Then, a flow-induced vibration test facility which simulates a hot leg piping with 1/3 scale has been fabricated. As a first step of the test series, this report describes outline of flow visualization test results.

著者

石谷 嘉英 中村 友道 佐郷 ひろみ 白石 直 渡壁 壽人 此村 守 山口 彰 藤井 正

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集 : JSME annual meeting

巻号頁・発行日

vol.2004, no.7, pp.105-106, 2004-09-04

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A 1/3scale flow-induced vibration test facility that simulates a hot-leg piping of the Japanese sodium-cooled fast reactor (JSFR) is used to investigate the pressure fluctuations of the pipe. To evaluate the flow-induced vibrations for the hot-leg and cold-leg pipes, the random force distributions along the pipe and their correlations are estimated. As the result, the power spectrum densities of pressure fluctuations are classified into four sections, the correlation lengths of axial direction into three sections, and the correlation lengths of tangential direction into four sections. The maximum flow-induced random vibration force in the pipe is estimated in the region of flow separation downstream the elbow.

著者

中村 友道 佐郷 ひろみ 白石 直 此村 守 山口 彰 藤井 正

出版者

一般社団法人日本機械学会

雑誌

年次大会講演論文集 : JSME annual meeting

巻号頁・発行日

vol.2004, no.7, pp.101-102, 2004-09-04

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1/10^<th> scale model flow test has been conducted to measure the fluid force acting on the upper internal structure in a sodium reactor. This model has already been constructed and it couldn't be re-arranged including its flow section. Then, the internal structure is supported with flexible rods to measure the response, preventing the effect on the flow pattern. The exciting force by flowing fluid is analyzed by solving an inverse problem, where the exciting force is obtained by screening the vibration characteristics from the responding vibration signal. Because the real exciting force has not known, two methods, from the acceleration response and from the strain gage attached on the supporting rods, are tried to obtain the same force, and they show a reasonable coincidence