Proppant placement behavior in nano-modified VES fracturing fluids considering wall Filtration loss

The transport and placement of proppant within fractures in the process of hydraulic fracturing significantly impact oilfield productivity. In this study, by using the Cross constitutive equation and the Eulerian-granular multiphase flow model, we conducted numerical simulations of sand-carrying flow within fractures with considering fluid filtration loss along the fracture wall. The model was experimentally validated using a custom-designed fracture test facility. The results indicate that, for Cross fluid, an increase in wall filtration loss rate leads to a gradual reduction in the volume fraction of proppant within the fracture, accompanied by a decrease in sand bank height although the overall difference is small. This study further confirms that considering wall filtration, the use of small-particle-size, low-density proppants significantly enhances their placement efficiency at the distal end of fractures and reduce the risk of sand blockage.