Pore-scale modeling of multicomponent, multiphase geofluids exhibiting partial miscibility – a fugacity-based lattice Boltzmann approach
Restricted (Penn State Only)
- Author:
- Soomro, Muzammil
- Graduate Program:
- Energy and Mineral Engineering (PHD)
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- February 20, 2023
- Committee Members:
- Jeremy Gernand, Program Head/Chair
Eric Greenwood, Outside Unit & Field Member
Luis Ayala H, Chair & Dissertation Advisor
Yashar Mehmani, Major Field Member
Russell Johns, Major Field Member - Keywords:
- Lattice Boltzmann Method
Thermodynamics
Phase Behavior
Black Oil
Fugacity
Gibbs Adsorption Isotherm
Adsorption
Multicomponent
Multiphase - Abstract:
- Pore-scale modelling of fluid flow has become increasingly important in geological applications like hydrocarbon recovery, carbon dioxide sequestration and hydrogen storage. Geofluids found in these setups are often composed of multiple chemical components and exhibit multiphase behavior. An important aspect of such multicomponent multiphase (MCMP) systems is the presence of interfacial mass transfer, or partial miscibility, whether to a small extent, which is usually approximated as immiscibility, or to a large extent. Pore-scale modelling of these partially miscible MCMP geofluids presents a wide range of complexities that need to be addressed and an array of physical phenomena that need to be captured, which is what this dissertation aims to tackle. A promising fluid dynamics tool that has found popularity in porous media applications is the lattice Boltzmann method (LBM), and this dissertation will extend the LBM to the flow of partially miscible MCMP geofluids. In this dissertation, we first start off by demonstrating that the LBM is a suitable candidate for our study by conducting a preliminary test which shows that the LBM can capture viscous and capillary forces. This is done by simulating the pore doublet model and matching the simulation results to theoretical predictions. Next, we address the issue of the computational cost associated with multicomponent LBM by introducing a component reduction scheme in the form of the binary black oil model applied at the pore-scale. Following that, we introduce an LBM model capable of handling partially miscible MCMP systems and accurately predicting phase density and composition according to multicomponent equations of state. We do this by introducing an LBM formulation based on the fugacity of each component. We present an extensive analysis of binary and ternary phase behavior using this fugacity-based LBM. Additionally, we show that the fugacity-based LBM can incorporate an important interfacial phenomenon: adsorption at the fluid-fluid interface. We demonstrate that the fugacity-based LBM predicts interfacial adsorption and is in quantitative agreement with Gibbs adsorption isotherm theory. Lastly, we present a fluid-solid interaction model for partially miscible MCMP fluids that is able to capture preferential wettability and absorption onto a solid surface.