Optimizing fluid viscosity for systems of multiple hydraulic fractures

Optimal hydraulic fracturing stimulations of horizontal oil and gas wells maximize created fracture surface area and/or maximize the uniformity of stimulation. Here, we use a new, rapidly-computing hydraulic fracture model to investigate how surface area and uniformity are impacted by interplay among multiple growing hydraulic fractures driven through permeable rocks by fluids of various viscosities. The results show the existence of a surface-area-optimizing viscosity that is large enough to control leak-off but not so large that leads to unnecessarily large fracture aperture.