Abstract:

Hydraulic fracturing real-time evaluation technology provides an effective way to understand formation and fracturing, assess the quality of fracturing construct, and ensure the safety of fracturing construction. In this paper, combined with numerical simulation and data analysis, a new 3D model of real-time fracture extension is established on the basis of the theories of fluid dynamics, linear elastic fracture mechanics and computational mathematics. This model satisfies the requirement of hydraulic fracturing real-time with the advantage of simple in form, precise and fast in computation. Considering the influence of proppant on the friction calculation of sand mixed fluids, a wellbore flow model is developed, which is more widely used and makes it no need of down-hole data acquisition. The authors also study the related data acquisition technology, and set three ways of acquiring data, which could realize the real-time acquisition of field data. In order to match the real wellhead pressure, an optimizing model and its automatic fitting methods for assessing formation and hydraulic fracturing parameters at real time is proposed. The parameters include fluid rheological properties, leakage levels with dynamic changes, fracture geometry and proppant distribution and migration. The application in Xinjiang oilfield in China showed that the presented technology can satisfy the requirements of fracturing, analyze and evaluate fracturing construction quality and guide fracturing design effectively.