Transportation and deposition of oval and cylindrical shaped proppant particles in complex-fracture systems

Hydraulic fracturing treatment can create complex fractures to provide oil and natural gas flow path. To achieve a high conductivity, the proppant should be placed properly in the fractures. Up to date, nearly all proppant materials used are spherical or nearly spherical particles and the effect of proppant shape is rarely reported. In this work, we investigate the flow, transport and deposition of non-spherical proppant particles in complex fractures. The results show that in the primary fracture, the packing patterns of ovals behave as spheres, but cylinders show a significant difference. Ovals can enter subsidiary fractures at a lower pump rate than cylinders and spheres. The effect of fluid viscosity on the packing pattern is also examined, revealing a significant influence in the primary fracture, but not much in the subsidiary fracture. The proppant transportation efficiency decreases with increasing the fluid viscosity for the conditions considered in this work.