Hydraulic fracturing is currently a necessary part of the unconventional hydrocarbon reserves development. The efficiency of hydraulic fracturing is influenced by a large number of factors, one of which is the quality of the near-fracture zone of the formation, the so-called fluid loss damage zone. The flow rate and productivity index of the well significantly depend on the parameters of this zone. Therefore, it is important to have a way to estimate these parameters. The following problem was considered: in an infinite reservoir saturated with a single-phase fluid, there is a well that is intersected by a symmetric vertical hydraulic fracture along its entire thickness. The formation around the fracture has a damaged zone that has reduced reservoir properties. The hydraulic connection between the reservoir and the well is realized only through the lateral surface of the fracture. At the initial moment of time, the pressure in the formation and the fracture is the same, and the well is put into production at a constant flow rate. The solution obtained by application of the Laplace integral transform method, is presented in the form of the dependence of the bottomhole pressure on time and the hydrodynamic parameters of the system reservoir – skin zone – hydraulic fracture. This expression is essentially a ‘type curve’ equation that can be used to solve inverse problems of reservoir hydrodynamics and interpretation problems of well testing. The solution includes a parameter that can be considered as a value that determines the additional pressure drop in the skin zone, which in its meaning coincides with the skin factor.
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