Petroleum Science >2015,??Issue 2:??304-315 DOI: https://doi.org/10.1007/s12182-015-0017-x
Numerical analysis of rock fracturing by gas pressure using the extended finite element method Open?Access
文章信息
作者：Majid Goodarzi,Soheil Mohammadi and Ahmad Jafari
作者單位：
Department of Civil Engineering and Geoscience, University of Newcastle, Newcastle upon Tyne NE1 7RU, UK;School of Civil Engineering, University of Tehran, Tehran 11365-4563, Iran;School of Mining Engineering, University of Tehran, Tehran 515-14395, Iran
投稿時間：2014-07-12
引用方式：Goodarzi, M., Mohammadi, S. & Jafari, A. Pet. Sci. (2015) 12: 304. https://doi.org/10.1007/s12182-015-0017-x
文章摘要
High energy gas fracturing is a simple approach
of applying high pressure gas to stimulate wells by generating
several radial cracks without creating any other
damages to the wells. In this paper, a numerical algorithm
is proposed to quantitatively simulate propagation of these
fractures around a pressurized hole as a quasi-static phenomenon.
The gas flow through the cracks is assumed as a
one-dimensional transient flow, governed by equations of
conservation of mass and momentum. The fractured
medium is modeled with the extended finite element
method, and the stress intensity factor is calculated by the
simple, though sufficiently accurate, displacement extrapolation
method. To evaluate the proposed algorithm,
two field tests are simulated and the unknown parameters
are determined through calibration. Sensitivity analyses are
performed on the main effective parameters. Considering
that the level of uncertainty is very high in these types of
engineering problems, the results show a good agreement
with the experimental data. They are also consistent with
the theory that the final crack length is mainly determined
by the gas pressure rather than the initial crack length
produced by the stress waves.
of applying high pressure gas to stimulate wells by generating
several radial cracks without creating any other
damages to the wells. In this paper, a numerical algorithm
is proposed to quantitatively simulate propagation of these
fractures around a pressurized hole as a quasi-static phenomenon.
The gas flow through the cracks is assumed as a
one-dimensional transient flow, governed by equations of
conservation of mass and momentum. The fractured
medium is modeled with the extended finite element
method, and the stress intensity factor is calculated by the
simple, though sufficiently accurate, displacement extrapolation
method. To evaluate the proposed algorithm,
two field tests are simulated and the unknown parameters
are determined through calibration. Sensitivity analyses are
performed on the main effective parameters. Considering
that the level of uncertainty is very high in these types of
engineering problems, the results show a good agreement
with the experimental data. They are also consistent with
the theory that the final crack length is mainly determined
by the gas pressure rather than the initial crack length
produced by the stress waves.
關鍵詞
-
Gas fracturing Numerical modeling Extended finite element Fracture mechanics