Abstract: In the process of hydraulic fracturing horizontal wells in the Dongsheng Gasfield, there is a lack of research on the proppant transport patterns within the main hydraulic fractures, leading to suboptimal reservoir stimulation effect. To address this issue, a visual parallel plate fracture simulation system was employed to conduct proppant placement experiments under different fracture extension directions within the main hydraulic fractures. The influence of displacement, sand ratio, fracturing fluid viscosity, and proppant particle size on sand dune morphology was simulated using Fluent software. The study shows that: The orientation of fracture propagation and the proppant placement are the primary factors affecting the growth pattern of sand dunes and the frontal placement efficiency. Compared to horizontal and upward fracture extensions, the height of the sand dune at the entrance is 1.79 times and 12.17 times when the fracture extends downward, with the frontal placement rates being 1.21 times and 6.09 times, respectively. The contribution of single fracture production is increased by 2% and 24%, respectively.Construction parameters do not influence the growth pattern of sand dunes; however, the pumping method of large-displacement and high-viscosity fracturing fluids can effectively reduce the time required for sand dunes to reach equilibrium height, thereby enhancing the migration capacity of proppant. The pumping method with high sand ratios and large particle sizes can achieve a more desirable main hydraulic fracture placement effect in a relatively short period. The research results can provide reference for the optimization of gas field fracturing process.

Key words: horizontal well, fracturing, fracture, proppant transport pattern, Dongsheng Gasfield