3D PRINTING AND DIGITAL ROCK PHYSICS FOR GEOSCIENCE APPLICATIONS

The mechanical and fluid flow properties in fractured and porous media are fundamental to predicting coupled multiphysics processes in the subsurface. Recent advances in experimental methods and multi-scale imaging capabilities have revolutionized our ability to quantitatively characterize geomaterials, which allows us to reach ever-increasing spatial resolution across scales. Digital rocks reconstructed from multiscale images (e.g., microCT images) and theoretical/stochastic generations are now routinely used to characterize petrophysical and mechanical properties across scales. Additive manufacturing, commonly known as 3D printing, is a fast-growing manufacturing technique that produces custom parts or whole products by printing materials by layers only where it is needed. For geoscience applications, 3D printing technology can be co-opted to print reproducible porous and fractured structures derived from CT-imaging of actual rocks and theoretical algorithms for experimental testing. The use of 3D printed microstructure allows us to overcome sample-to-sample heterogeneity that plague rock physics testing and to test material response independent from pore-structure variability. Integration of imaging, digital rocks and 3D printing potentially enables us to develop a new workflow for understanding coupled petrophysical and mechanical processes in a well-defined setting with the improved reproducibility, enabling full characterization and thus connection of physical phenomena to structure. In this talk we will present our preliminary works with coupled multiscale experimental and numerical analysis using 3D printed fractured rock specimens. In particular, we discuss the processes of selection and printing of fractured specimens and small cylinder cores with various materials to study fluid flow characterization and geomechanical testing. We will also discuss the innovative advancement of 3D printing techniques applicable for coupled processes in the subsurface.

Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.