Method for Preparing Prefabricated Fractures in Hydraulic Fracturing Simulation Test Specimen

Abstract

The invention provides a method for preparing preset cracks in a hydrofracture simulation specimen. The simulation specimen is formed by splicing a plurality of internal chunks. The method comprises the following steps: firstly determining sizes, shapes and mutual positions of internal chunks for forming the simulation specimen according to crack morphology of a to-be-simulated stratum; manufacturing an internal chunk module according to the size and shape of each internal chunk; selecting a casting material to cast the internal chunks; then splicing and combining the internal chunks according to the mutual positions, wherein preset cracks are formed by contact surfaces among the intern chunks; casting a cladding layer on the periphery of the spliced combined component, thus forming a simulation specimen containing a plurality of preset cracks. The method can set the preset cracks in any quantity and any shapes in the simulation specimen so that the simulation specimen is more similarto the actual stratum so as to improve the accuracy of the simulation test.

Description

technical field [0001] The invention relates to a hydraulic fracturing simulation test piece used in a physical simulation experiment of a large-scale true triaxial hydraulic fracturing laboratory, in particular to a method for preparing pre-set cracks in a hydraulic fracturing simulation test piece. Background technique [0002] Hydraulic fracturing has been widely used in modern petroleum engineering as the main measure for increasing oil and gas production, and has played an important role in the production of low-permeability oil and gas reservoirs. At the same time, it has also been used in other fields such as geothermal resources and nuclear waste storage. [0003] Hydraulic fracturing is a complex engineering phenomenon of fluid-solid coupling under deep formation conditions. With the continuous development of the world's petroleum industry, new requirements are put forward for the technical performance of hydraulic fracturing. In order to improve the success of hyd...

AI Technical Summary

Problems solved by technology

Since the construction object of hydraulic fracturing is the formation rock located at a depth of several thousand meters underground, it is difficult and expensive to obtain the actual core, and in many cases it is limited to the drilling technology, and the core taken out is small in size and difficult to obtain. It meets the size requirements of large-scale (30cm×30cm×30cm) fracturing experiments, so artificial specimens become an ideal choice

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