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Article information
2019 , Volume 24, ¹ 4, p.38-55
Lapin V.N.
Model for drilling mud losses into a system of natural fractures applied to the problem of estimation for parameters of fractured porous medium
The loss of drilling mud in a rock during wellbore drilling is considered. The goal is to build a methodology for determining parameters of a fractured porous medium by analyzing the drilling mud loss rate and wellbore pressure as functions of time. To develop the methodology, the optimization problem for finding the fracturedporous medium parameters based on the pressure and mud loss dependences versus time is formulated. The direct problem is to find the dependence of the mud loss as a function of time using known parameters of the reservoir, the mud rheology and the pressure in the wellbore. To solve the direct problem, a model of mud loss to the system of natural fractures is proposed. The model describes the radial flow of mud in the natural fracture, the deformation of fracture sides under the pressure from mud and the leak-off of mud into the rock. The model has been verified by comparison with analytical solutions. An analogy with the model of fluid filtration into a dual porosity medium is shown. As a result of research, it was shown that, using the data of drilling mud losses, it is possible to find only one of a pair of parameters characterizing a fractured-porous medium, namely the width of cracks with a known amount or permeability with known porosity.
[full text] [link to elibrary.ru]
Keywords: radial flow in the channel, viscoplastic fluid, fractured porous medium, loss of drilling mud
doi: 10.25743/ICT.2019.24.4.004
Author(s):
Lapin Vasily Nikolaevich
PhD.
Office: Institute of Computational Technologies SB RAS
Address: 630090, Russia, Novosibirsk, Ac. Lavrentjev Ave. 6,
Phone Office: (383) 3307373
E-mail: lapin@ict.sbras.ru
References:
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Bibliography link:
Lapin V.N. Model for drilling mud losses into a system of natural fractures applied to the problem of estimation for parameters of fractured porous medium // Computational technologies. 2019. V. 24. ¹ 4. P. 38-55
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