Three‐dimensional visualization experimental study on proppant transportation and placement in the Hi‐way channel hydraulic fracturing technique

Abstract

The pattern of placement of the proppant in the fracture determines the stimulation and success of the surgery. Using a three‐dimensional visual parallel plate fracture model capable of simulating fracture height, length, and variable fracture width, we experimentally investigate the impact of fiber loading, fracture fluid viscosity, sand concentration, pulse time, perforation pattern, and injection rate on proppant transport, placement pattern, and access rate. Experimentally and visually, the migration process and the morphology of the proppant placement in the fracture were assessed. The formation laws of stable support columns and well‐shaped high conductivity fracture channels in fractures have been elucidated. Experimental results show that increasing the fiber concentration improves the channel rate and the proppant mass is large and stable. The channel rate increases with the viscosity of the fracturing fluid, and it is difficult to form a perfect channel when the viscosity is small. If the constructive displacement is too slight or too large, it will not favor the formation of a Hi‐way channel in the fracture. The optimal design displacement is 4.5 m3/min. When the proppant concentration is low, the passage rate is large, but the stability of proppant mass is poor under the scour of large displacement, the conductivity is low under the high closure pressure, the proppant concentration is too high, the suspension is difficult, the settlement rate is large, and it is difficult to form a large passage. The current column and the passage rate are larger for pulse times of 15–20 s. Cluster perforations are better than large continuous perforations. The higher the number of clusters in the same number of holes, the higher the channel rate. The formation laws of stable support pillars and well‐shaped high conductivity fracture channels in fractures have been elucidated, which can be useful for efficient stimulation of oil and gas reservoirs.

Simulation and solution of a proppant migration and sedimentation model for hydraulically fractured inhomogeneously wide fractures

“…), different proppant types (grain size (Sahai and Moghanloo, 2019), sphericity (Zhang, 2017), density (Hao, 2018;Li, 2018)), different carrying fluid viscosities (Anschutz et al, 2023;Zhang et al, 2021), different injection flow rates (Liang et al, 2018;Liu et al, 2019;Zhang et al, 2023b), different fracture types (eg. even-wide fractures (Liang et al, 2018), elliptical shape fractures (Zhu et al, 2023) or complex fractures (Li et al, 2024;Qu et al, 2023;Xiang and Li, 2023)) were also investigated in the indoor tests to obtain the proppant accumulation distribution under various conditions, which then served as a reference for optimization of the parameters of the hydraulic fracturing in the field, Bai and Li (2023) and Zhou et al (2023) did research on the friction and settling characteristics by indoor tests to provide parameters for numerical model. However, the model equipment of indoor tests during hydraulic fracturing does not fully simulate the actual situation of a fracture morphology in the subsurface.…”

“…Huang et al (2021) proposed a continuum model for simulating proppant transport and fluid flow in hydraulic fractures. Isaev et al (2023) proposed adaptive seeding/reseeding methods with exact integration of particles trajectories and local time step refinement in the vicinity of injection zones In these studies, equations describing the migration and sedimentation of proppant were derived based on the solid-liquid coupling relationship and sedimentation law during proppant flow (Hu et al, 2023;Li et al, 2023;Shi, 2016), and most of them were simulated with CFD-DEM (Gong et al, 2023;Liu et al, 2019;Lv et al, 2023;Shi, 2016;Tong and Mohanty, 2016;Xiang and Li, 2023;Zhang et al, 2022Zhang et al, , 2023aZhu et al, 2023) or CFD-XFEM software (Brannon et al, 2005;Qu et al, 2022Qu et al, , 2023Zhang et al, 2023b) such as fluent for two-dimensional and pseudo three-dimensional model. Through numerical simulations of parameters (Hang et al, 2023;Suri et al, 2019Suri et al, , 2020b based on different fracturing fluids and proppant morphologies, the velocity, concentration and pressure distribution of the proppant within the fracture were obtained, and proppant migration and sedimentation patterns were also derived for different fracture morphology parameters and proppant and fluid parameters.…”