Benchmarking the Viability of 3D Printed Micromodels for Single Phase Flow Using Particle Image Velocimetry and Direct Numerical Simulations

Using 3D-printed fracture networks to obtain porosity, permeability, and tracer response datasets

An in-depth understanding of flow through fractured media is vital to optimise engineering applications, including geothermal energy production, enhanced oil recovery, CO2 storage, and nuclear waste disposal. Advances in 3D-printing technologies have made it possible to generate 3D printed fracture networks with different fracture characteristics. By performing fluid flow experiments in the 3D-printed fractured networks, the impact of the fracture parameters, such as the density, orientation, aperture, dip, and azimuth, on the overall flow can be investigated. This data article contains a detailed description of the framework followed to design fractured networks with different fracture parameters and to create 3D-printed samples, including fracture networks. Furthermore, it contains the experimental protocols used to measure the porosity, permeability, and tracer responses of the 3D-printed samples. The generated datasets provided include geometry data describing the fracture networks, as well as porosity, permeability and tracer response data obtained from flow experiments conducted in the fracture networks.

Developing synthetic sandstones using geopolymer binder for constraining coupled processes in porous rocks

There is a current need for developing improved synthetic porous materials for better constraining the dynamic and coupled processes relevant to the geotechnical use of underground reservoirs. In this study, a low temperature preparation method for making synthetic rocks is presented that uses a geopolymer binder cured at 80 °C based on alkali-activated metakaolin. For the synthesised sandstone, the key rock properties permeability, porosity, compressive strength, and mineralogical composition, are determined and compared against two natural reservoir rocks. In addition, the homogeneity of the material is analysed structurally by micro-computed tomography and high-resolution scanning electron microscopy, and chemically by energy dispersive X-ray spectroscopy. It is shown that simple, homogenous sandstone analogues can be prepared that show permeability-porosity values in the range of porous reservoir rocks. The advance in using geopolymer binders to prepare synthetic sandstones containing thermally sensitive minerals provides materials that can be easily adapted to specific experimental needs. The use of such material in flow-through experiments is expected to help bridge the gap between experimental observations and numerical simulations, leading to a more systematic understanding of the physio-chemical behaviour of porous reservoir rocks.

Stereolithography 3D Printer for Micromodel Fabrications with Comprehensive Accuracy Evaluation by Using Microtomography

Micromodels are important for studying various pore-scale phenomena in hydrogeology. However, the fabrication of a custom micromodel involves complicated steps with cost-prohibitive equipment. The direct fabrication of micromodels with a 3D printer can accelerate the fabrication steps and reduce the cost. A stereolithography (SLA) 3D printer is one of the best options because it has sufficient printing performance for micromodel fabrication and is relatively inexpensive. However, it is not without drawbacks. In this report, we explored the capability of an SLA 3D printer for micromodel fabrication. Various parameters affecting the printing results, such as the effects of geometries, dimensions, printing axis configurations, printing thickness resolutions, and pattern thicknesses were investigated using microtomography for the first time. Eventually, the most optimal printing configuration was then also discussed. In the end, a complete micromodel was printed, assembled, and used for fluid displacement experiments. As a demonstration, viscous and capillary fingerings were successfully performed using this micromodel design.