Reservoir Simulation

Overview

Led by Dr. Kamy Sepehrnoori, the objectives of this research project include the development, testing, verification, and application of reservoir simulators for oil and gas recovery processes. The reservoir simulators developed in this project are used as test beds for new process physics, computational algorithms, physical property models, and other scientific purposes. Our most recent code developments have been concentrated on the design and implementation of a compositional reservoir simulator called the General Purpose Adaptive Simulator (GPAS) for application on parallel supercomputers or clusters of PCs. This code is intended for the simulation of miscible gas flooding as well as chemical flooding. The ongoing projects include model developments for wettability alteration, conformance control using microgels, predictive reservoir souring, geomechanics, unstructured gridding, naturally fractured reservoirs, and compositional fluid flow in wellobores including asphaltene precipitation and deposition. We address the application of our codes as well as the commercial reservoir simulators for solving generic field simulation studies. The amount of resources spent on each research topic is decided based on funds available as well as the participants' interests.

Development and Maintenance of Simulators for EOR Processes

The objective of this research is to develop a general-purpose adaptive reservoir simulator (GPAS) for parallel supercomputers and clusters of PCs. The simulator is designed to perform accurate, efficient high-resolution simulations of fluid flow in permeable media for large complex problems.

The main tasks in this project are to maintain and expand the capability of our compositional equation-of-state reservoir simulator (UTCOMP). The ongoing research will focus on:

The Integrated Reservoir Simulation System (IRSS) is a compilation of software and hardware on a single processor, or a cluster of processors, running Linux to solve numerous oil reservoir problems.

Model Development

The production of hydrocarbons often involves a concurrent gas and liquid (oil/water) flow in the wellbore. As a multiphase/multicomponent gas-oil mixture flows from the reservoir to the surface, pressure, temperature, composition, and liquid holdup distributions are interrelated.

Conformance control methods using polymer gel treatments have been widely used to reduce water production as well as improve sweep efficiency. Conformance control strategies include

The goal of this project is to add the capability of adding a compositional parallel geomechanics module in GPAS. The objectives are

The electrical low frequency heating is a thermal recovery process that has been proposed for high viscous and heavy oil reservoirs.

Waterflooding as a secondary oil recovery method is still the most commonly used technique for fluid injection since 1865.

Carbonate rocks account for more than half the world's hydrocarbon proven reserves. Oil recovery from these reservoirs is a challenge due to their complex nature. Several enhanced oil recovery techniques have been proposed for improving the oil recovery from carbonate reservoirs.

The objectives of this project have been the numerical representation of naturally fractured reservoir using the following approaches:

Reservoir souring is an increase in hydrogen sulfide concentration during water injection operations. H2S content reduces the value of produced hydrocarbon, in addition to being a health and safety issue. Nitrate injection is an effective method to prevent the formation of H2S.

While the equation of state (EOS) is extensively used for the characterization of the phase behavior of multi-component fluid mixtures, such use of EOS to characterize the phase behavior of microemulsion systems has so far not been possible, due to the complex micro-structures formed by the oil a

We have developed and implemented an element-based finite volume (EbFV) method for unstructured grids using mixed elements. The EbFV method has been implemented and tested in both GPAS and UTCHEM.

Laboratory surfactant/alkali and hot water floods have shown great potential in increasing oil recovery for reservoirs that are naturally fractured and have low permeability and mixed-wet matrix rocks.

Oil recovery from fractured carbonate reservoirs by water flooding is often inefficient due to the commonly oil-wet nature of these rocks and the lack of sufficient spontaneous capillary imbibition driving force to push oil out from the matrix to the fracture network.

Modeling and Simulation

Reservoir simulation is an effective method to help engineers estimate the oil and gas resources and nearly all major reservoir development decisions are made based in some ways on simulation results.

A simulation study was conducted using Eclipse reservoir simulator for nitrogen injection into a naturally fractured reservoir. Both homogenized permeability and dual porosity models were used to represent the reservoir for the gas injection process.

We developed a platform that distributes multiple reservoir simulations on a cluster of CPUs.