Pore-Scale Simulations and Digital Rock Physics

Understanding pore-scale fluid flow is critical for guiding field-scale production of unconventional reservoirs. In this chapter, the recent progress on pore-scale simulations and digital rock physics of fluid flow in unconventional reservoirs is presented. First, the physics of flow in unconventional rocks that deviates from the continuum fluid mechanics theory is discussed. Then recent developments in modifying the lattice Boltzmann methods to account for the nanoscale physics are presented in detail. Finally, various simulation examples using the modified lattice Boltzmann methods are given, including gas slippage, adsorption, surface tension, water flow, two phase flow considering slip effect, and vapor condensation. It is shown that through proper modification of boundary conditions, collision operators, and/or force terms, the lattice Boltzmann method can be an effective tool to simulate physics of flow in unconventional reservoir rocks at the pore scale.