Sand-carrying thresholds of viscous slickwater:Weissenberg number-based prediction and field applicationOA

The complex viscoelastic and shear-thinning behavior of slickwater fracturing fluids imposes competing effects on proppant transport,complicating the prediction of sand-carrying capacity and increasing the sand plugging risk.This study quantifies slickwater elasticity over a range of shear rates using the Weissenberg number(Wi)and establishes a fracture-scale shear-rate calculation method to estimate elastic energy at different flow velocities.The results show that:(1)the Wi strongly correlates with sand-carrying capacity,demonstrating its effectiveness in characterizing elastic-dominated transport behavior;(2)fracture experiment identify distinct settling-rate thresholds for slickwater systems with different polymer concentrations;(3)at these thresholds,fluids transporting equivalent proppant volumes exhibit identical elastic energies,indicating a the existence of a critical elastic-energy requirement for stable proppant suspension;(4)elastic-energy thresholds are established for three sand concentrations,allowing rapid prediction of sand-carrying capacity across slickwater systems with different viscosities;and(5)a field construction strategy derived from the predicted operating window is validated through field trials conducted both within and outside this window,with close agreement observed between the predicted and actual proppant-transport performance.This study provides a quantitative and practical framework for optimizing slickwater fracturing operations.