Unconventional reservoirs require segmented multi-cluster fracturing technology for commercial development. Due to the settling and inertial effects of proppant particle flow, even if the fracturing fluid is evenly distributed among each perforation, the proppant may still be unevenly distributed. However, the uniform distribution of proppant in multi-fracture is a favorable condition for high-yield gas wells. Based on the proppant dynamics model in the wellbore, coupled with the non-uniform fracture propagation model, a mathematical model of proppant wellbore transportation flow under multi-fracture is established. Through numerical calculations, the proppant transport and distribution mechanism are studied. The study shows that due to gravity, distribution in the upstream is more uniform, and the proppant in the downstream gradually settles and most particles flow toward the bottom. Proppant distributed in each cluster is affected by the flow rate of slurry to a certain extent, and is also controlled by its own properties. The turning efficiency determines the inflow of proppant in perforations. Increasing the pump rate can alleviate gravity but reduce turning efficiency. The perforation azimuth primarily regulates the flow of proppant into downstream perforations. The research results can provide theoretical guidance for the design of proppant transport and cluster perforation in hydraulic fracturing.
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