Pressure Losses in Fracture-Dominated Reservoirs: the Wellbore Constriction Effect

Abstract

Improved energy production from many types of energy reservoirs such as hot dry rock geothermal as 1 as hydraul ically fractured oil, gas, and other geothermal reservoirs requires a better understanding of the fluid mechanics in the vicinity of the intersection. Typically, the aperture (smallest dimension) of a hydraulic fracture is only of the order of 1 (0.04 in.) so that reasonable energy production rates from geothermal systems require fairly large flow velocities within the fractures, particularly so as the wellbore-fracture intersection is The high velocities and accelerations result in often turbulent, flow and increased pressure losses. These flow phenomena investigated experimentally for the simple case where the fracture plane and the wellbore drilling axis are orthogonal and the implication of these experimental results are examined by investigating the pressure losses in a hot dry rock reservoir.