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Analysis of fracturing fluid system, effect of rock mechanical properties on fluid selection

Laurain A.

AGH Drilling, Oil, Gas

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2014

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Vol. 31, no. 1

167--178

EN

Hydraulic fracturing treatments of shale gas reservoirs is pumping process in which millions of gallons of fracturing fluids mixed with proppant materials and thickening agents are pumped into the target shale formation. Fluids are used to create the fractures in the formation and to carry a propping agent which is deposited in the induced fractures to keep them from closing up. Type and percentage of chemical additives that used in a typical fracture treatment varies depending on the conditions of well being fractured. A series of chemical additives are selected to impart a predictable set of properties of the fluid, including viscosity, friction, formation-compatibility, and fluid-loss control. Each component in fracturing fluids serves a specific, engineered purpose and geological structure of rock. The properties of fracturing fluid are very important in the creation and propagation of the fracture. For suc-cessful stimulation fracturing fluid mustto have certain chemical and physical properties. Study of the properties fracturing fluids has ahuge role inthe processes of shale gas extraction. In scientific literature indicates that hydraulic fracturing fluid performance became a prevalent research topic in the late 1980s and the 1990s. The majority of literature pertaining to fracturing fluids related to their operational efficiency and classification. Some of the existing literature offer information regarding the basic chemical components present in most of these fluids. This paper will discuss types of fracturing fluids and it components that may be used for hydraulic fracturing. Comprehensive history of the evolution of hydraulic fracturing fluids in the oil and gas industry plays a significant part in research. This work summarizes requests for fracturing fluids. In addition, this paper shows effect of rock mechanical properties on fracturing fluid selection.

2

Electrical impedance tomography: from topology to shape

Hintermuller M., Laurain A.

Control and Cybernetics

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2008

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Vol. 37, no 4

913-933

EN

A level set based shape and topology optimization approach to electrical impedance tomography (EIT) problems with piecewise constant conductivities is introduced. The proposed solution algorithm is initialized by using topological sensitivity analysis. Then it relies on the notion of shape derivatives to update the shape of the domains where conductivity takes different values.

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A level set method in shape and topology optimization for variational inequalities

Fulmański P., Laurain A., Scheid J. F., Sokołowski J.

International Journal of Applied Mathematics and Computer Science

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2007

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Vol. 17, no 3

413-430

EN

The level set method is used for shape optimization of the energy functional for the Signorini problem. The boundary variations technique is used in order to derive the shape gradients of the energy functional. The conical differentiability of solutions with respect to the boundary variations is exploited. The topology modifications during the optimization process are identified by means of an asymptotic analysis. The topological derivatives of the energy shape functional are employed for the topology variations in the form of small holes. The derivation of topological derivatives is performed within the framework proposed in (Sokołowski and Żochowski, 2003). Numerical results confirm that the method is efficient and gives better results compared with the classical shape optimization techniques.