DFN Simplifying Approaches Applied to the Discrete Element Modeling of Thermo-Hydro-Mechanical Processes

Riahi, Azadeh (Itasca Consulting Group, Inc.) | Varun, Branko Damjanac (Itasca Consulting Group, Inc.)


As computing power increases, numerical modeling of large-scale engineering problems of a discrete nature becomes more feasible. While there are many applications where a fractured rock mass can be represented as a continuum with equivalent properties, there are applications in which explicit representation of a discrete fracture network (DFN) is key to correct assessment of rock mass response. Engineering of unconventional resources is an application area where natural fractures and computational methods that can explicitly represent DFNs is gaining attention. Gas extraction from tight shale formations is often controlled by the interaction of hydraulic fractures with the preexisting DFN (Walton and McLennan, 2013). In Enhanced Geothermal Reservoirs (EGS), success of the stimulation and production phases depends on understanding the role and response of fractures to cold water injection. In both applications, fracture heterogeneity and flow channeling is key to reservoir performance.