A Numerical Study on Water Well Resonance Induced by Pre-earthquake signals
Date Issued
2008
Date
2008
Author(s)
Chen, Ding-Jia
Abstract
Wang (2006) used regular perturbation method and separation of variables method to prove that the incident flow of the tiny pressure wave of the pre-earthquake signals passing through confined aquifer then penetrating into the well causes the occurrence of resonance at free surface. And only the radius of well can affect resonance frequency. This study tries to improve the shortcoming of analytic solution what Wang (2006) used. Setting a movable hole on the screen of well and applying three dimensional linear boundary element method (BEM) to solve problem of how the opening level of hole affects the flow inside and outside the well.arcy’s law and the small amplitude wave theory are adopted in this study to investigate the wave fields in the confined aquifer and in the water well respectively. In this study, it is assumed that the water in the well is incompressible, inviscid and irrotational, and the water outside the well is porous-media fluid with rigid structure.his study indeed finds the mechanism of resonant phenomenon of pre-earthquake signals, and also finds the relationship between the size of screen hole and the velocity potential on the screen hole to be linear. Besides, this study tries to find that when the screen hole of the well is very small whether diffraction happens outside the well or not. According to the result, diffraction doesn’t happen outside the well.fter setting this numerical model, we can get the flow field of well which has a movable hole through putting a known pre-earthquake signal incident wave. The study is be helpful in analyzing the well resonance and designing the observing water wells as the earthquake alert system.
Subjects
pre-earthquake signal
confined aquifer
water well
Boundary Element Method
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-97-R95521327-1.pdf
Size
23.32 KB
Format
Adobe PDF
Checksum
(MD5):5cacb2839089ec424a15e6fb39fa0a68