TY - JOUR

T1 - Effect of fluid viscosity, permeability of rock and crack interfacial stiffness on dynamic response of a geothermal reservoir crack (penny-shaped crack model)

AU - Ito, Shin

AU - Hayashi, Kazuo

N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.

PY - 1998

Y1 - 1998

N2 - In order to clarify the dynamic response of a fluid-filled crack in the earth's crust, dynamic elastic response of a penny-shaped fluid-filled crack is studied, emphasizing the effect of fluid viscosity, permeability of rock and the stiffness due to contact between the asperities on the upper and lower surfaces of the crack. It is revealed that the eigen angular frequencies normalized by Cr/aCr: S wave phase velocity, a : crack radius) are governed primarily by the crack interfacial stiffness. The aspect ratio, i. e., the ratio of the crack radius to the initial aperture of the crack, has only weak effects on the normalized eigen angular frequencies except for the case of a crack that is completely open initially. It is also revealed that, for larger crack interfacial stiffness, the normalized eigen angular frequencies become smaller with permeability and attenuation becomes stroger with permeability. When crack interfacial stiffness is absent, permeability has weak effect on the normalized eigen angular frequencies and intensity of attenuation.

AB - In order to clarify the dynamic response of a fluid-filled crack in the earth's crust, dynamic elastic response of a penny-shaped fluid-filled crack is studied, emphasizing the effect of fluid viscosity, permeability of rock and the stiffness due to contact between the asperities on the upper and lower surfaces of the crack. It is revealed that the eigen angular frequencies normalized by Cr/aCr: S wave phase velocity, a : crack radius) are governed primarily by the crack interfacial stiffness. The aspect ratio, i. e., the ratio of the crack radius to the initial aperture of the crack, has only weak effects on the normalized eigen angular frequencies except for the case of a crack that is completely open initially. It is also revealed that, for larger crack interfacial stiffness, the normalized eigen angular frequencies become smaller with permeability and attenuation becomes stroger with permeability. When crack interfacial stiffness is absent, permeability has weak effect on the normalized eigen angular frequencies and intensity of attenuation.

KW - Acoustic emission

KW - Dynamic response

KW - Elastic wave

KW - Elasticity

KW - Geothermal energy

KW - Geothermal reservoir crack

KW - Stress wave

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U2 - 10.1299/kikaia.64.1843

DO - 10.1299/kikaia.64.1843

M3 - Article

AN - SCOPUS:71249113688

VL - 64

SP - 1843

EP - 1848

JO - Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A

JF - Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A

SN - 0387-5008

IS - 623

ER -