Variational Phase-Field Modeling of Hydraulic Fracture Interaction With Natural Fractures and Application to Enhanced Geothermal Systems

Publikationen: Beitrag in FachzeitschriftArtikelForschung(peer-reviewed)

Autoren

  • Baptiste Lepillier
  • Keita Yoshioka
  • Francesco Parisio
  • Richard Bakker
  • David Bruhn

Externe Organisationseinheiten

  • Technische Universität Delft
  • Helmholtz Centre for Environmental Research‐UFZ, Leipzig
  • Technische Universität Bergakademie Freiberg

Abstract

In every tight formation reservoir, natural fractures play an important role for mass and energy transport and stress distribution. Enhanced Geothermal Systems (EGS) make no exception, and stimulation aims at increasing the reservoir permeability to enhance fluid circulation and heat transport. EGS development relies upon the complex task of predicting accurate hydraulic fracture propagation pathway by taking into account reservoir heterogeneities and natural or preexisting fractures. In this contribution, we employ the variational phase-field method, which handles hydraulic fracture initiation, propagation, and interaction with natural fractures and is tested under varying conditions of rock mechanical properties and natural fractures distributions. We run bidimensional finite element simulations employing the open-source software OpenGeoSys and apply the model to simulate realistic stimulation scenarios, each one built from field data and considering complex natural fracture geometries in the order of a thousand of fractures. Key mechanical properties are derived from laboratory measurements on samples obtained in the field. Simulations results confirm the fundamental role played by natural fractures in stimulation's predictions, which is essential for developing successful EGS projects.

Details

OriginalspracheEnglisch
Aufsatznummere2020JB019856
Seitenumfang20
FachzeitschriftJournal of geophysical research
Jahrgang125.2020
Ausgabenummer7
DOIs
StatusVeröffentlicht - Jul 2020
Extern publiziertJa