2016 Fiscal Year Final Research Report
Origin of volcanic tremor: A new hypothesis of flow-induced vibration
Project/Area Number |
26610138
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Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Multi-year Fund |
Research Field |
Solid earth and planetary physics
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Research Institution | The University of Tokyo |
Principal Investigator |
Sakuraba Ataru 東京大学, 大学院理学系研究科(理学部), 助教 (50345261)
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Project Period (FY) |
2014-04-01 – 2017-03-31
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Keywords | 境界要素法 / 弾性体力学 / 流体力学 / 線形安定解析 / 火山性微動 / 流れ誘起振動 / マグマ |
Outline of Final Research Achievements |
An attempt is made to experimentally and numerically verify a hypothesis that volcanic tremor is originated from flow-induced vibration of an underground magma conduit. A tank filled with a gel medium that includes a vertical plate-like conduit is prepared and a flow of a viscous fluid is maintained through the conduit; but no self-oscillation is observed. Linear stability analysis is made for a flow through a cylindrical conduit with an elliptic cross section. It is shown that a Rayleigh wave of which a wavelength is as long as the major axis of the ellipse can be destabilized at a significantly slow flow speed. This suggests that there might be a relation between the facts that a natural dike has an upper limit in its width and that there is un upper limit in oscillation period of volcanic tremor.
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Free Research Field |
地球内部ダイナミクス
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