1998 Fiscal Year Final Research Report Summary
This research has investigated the above-mentioned process resulting in cavitation erosion step by step.
| Project/Area Number |
09450372
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
船舶工学
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| Research Institution | The University of Tokyo |
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Principal Investigator |
KATO Hiroharu The University of Tokyo, Environmental & Ocean Eng., Prof., 大学院・工学系研究科, 教授 (00010695)
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| Co-Investigator(Kenkyū-buntansha) |
MAEDA Masatsugu The University of Tokyo, Environmental & Ocean Eng., Assistant, 大学院・工学系研究科, 助手 (60219277)
KOMURA Takashi The University of Tokyo, Environmental & Ocean Eng., Assistant, 大学院・工学系研究科, 助手 (10010894)
SATO Tohru The University of Tokyo, Environmental & Ocean Eng., Assoc.Prof., 大学院・工学系研究科, 助教授 (30282677)
MIYATA Hideki The University of Tokyo, Environmental & Ocean Eng., Prof., 大学院・工学系研究科, 教授 (70111474)
YAMAGUCHI Hajime The University of Tokyo, Environmental & Ocean Eng., Assoc.Prof., 大学院・工学系研究科, 助教授 (20166622)
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| Project Period (FY) |
1997 – 1998
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| Keywords | cavitation / Erosion / Prediction / Impact Pressure / Bubble Collapse / Sheet Cavitation / Cloud Cavitation |
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| Research Abstract |
In terms of the total volume of sheet cavity, which turns into the total vapor volume of initial cloud cavity, it is necessary to know evaporation rate at the sheet cavity surface which is vapor/liquid interface. Thus, the evaporation rate at cavity surface has been predicted by measuring the temperature distribution along a sheet cavity generated in high temperature and high pressure water where the thermodynamic effect due to evaporation appears more clearly.
Using a high speed video, the whole cavity behavior has been observed in detail. The frequency of cloud cavity shedding and the size and shape of the clouds have been measured. Also, a laser holography technique has been applied to measure the number and size of the bubbles in a could cavity.
Cavitation impact force sensors developed and fabricated by ourselves have been used to measure the impactive forces due to collapse of cloud cavities. A high speed video has been taken at the same time with frame rate of 40,500 fps. Behavior of cloud cavity collapse has been investigated in detail with correlation to the time history of the impact force taken into account.
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