Sharif Digital Repository

The success of oil recovery depends, among other factors, on the ability to provide reliable simulations of the reservoir performance. The reservoir dynamics are usually modeled by a distributed parameter dynamic system whose parameters represent the petrophysical properties of the reservoir. A proper characterization of those reservoir properties is fundamental for an accurate reservoir simulation. The petrophysical properties are highly heterogeneous and only a limited number of measurements are available at certain locations in the reservoir. Therefor, in ordet to obtain accurate prediction of the reservoir performance, it is essential to possess reliable estimates of the petrophysical... 

Enhanced oil recovery (EOR) techniques are gaining more attention worldwide as the proved oil is declining and the oil price is hiking. Although many giant oil reservoirs around the world were already screened for EOR processes, the main challenges such as low sweep efficiency, costly techniques, possible formation damages, transportation of huge amounts of EOR agents to the fields especially for offshore cases and the lack of analyzing tools in traditional experimental works, hinder the proposed EOR process.It has been shown that recently, nanoparticles are attractive agents to enhance the oil recovery at the laboratory scale.
In this study TiO2 nanoparticles were used to improve... 

Oil reservoir simulation serves an important role in forecasting oil production. This forecast, in turn, helps to devise a production scheme for hydrocarbon reservoirs which is one of main objectives of reservoir management team. In this research, using the idea of logarithmic distribution of reservoir fluid pressure around a wellbore, a new method for simulation of naturally fractured reservoir is developed. This method is shown to be more fast and accurate than conventional methods in reservoir simulation. In this method Dual-Porosity formulation is used for description of fluid flow in fractured reservoirs. The governing equations then were discretized by Galerkin Finite element method in... 

This thesis introduces a fast and accurate two-phase reservoir flow simulation procedure. The speed up is achieved by an upscaling technique where coarsening is applied to the detailed geological reservoir descriptions. This process results to two major error sources affecting the simulation accuracy significantly. The homogenization error is appeared when coarse scale data, such as equivalent permeability, is calculated from the available fine grid model information. It is shown that the error can be reduced adjusting coarse grid (non-uniform Cartesian) distribution. For the first time in this study, the grid distribution optimization is done based on “vorticity” map. In particular, the... 

Rapid variation in permeability with strong anisotropy are common features in subsurface reservoirs. When formulating a finite-volume pressure equation scheme, continuous normal flux and pressure are key physical constraints that must be imposed at control-volume interfaces, across which strong discontinuities in permeability can occur.
The derivation of algebraic flux continuity conditions for full-tensor discretization operators has lead to families of efficient locally conservative flux-continuous control-volume distributed (CVD) finite- volume schemes for determining the discrete pressure and elocity fields in subsurface reservoirs [5, 9, 11, 13].
When applying these... 

Naturally Fractured Reservoirs (NFRs) play an important role in petroleum industry and the global economy.. The reservoirs of the most complex geological structures in petroleum engineering science, on the other hand the largest sources of hydrocarbons are considered throughout the world and especially in our country. Therefore, characterization and modeling them frst step to develop best practices for hydraulic fracturing gap, optimal design of production Method and evaluate potential reservoirs. Physics of the present work is 2D two-phase immiscible flow under gravittational effect through fractured porous media and the most practical formulas for transfer function in dual porosity-dual... 

In this paper we have tried to mention a proper method of upscaling permeability data in a typical Iranian reservoir. Firstly a literature review is made on some common upscaling methods witch have been used so far. We introduced common upscaling methods like full tensor method, streamline method, stone method , vertical equilibrium method and also Kyte & Berry method. Additionally we have explained their advantages and also disadvantages. After selecting two upscaling methods, Kyte & Berry method and vertical equilibrium method, we applied these algorithms for upscaling of permeability data of Soroosh Oil Field. Soroosh oilfield is a heavy oil, Iranian reservoir located in Persian Gulf.... 

The main goal of petroleum reservoir simulation is finding of Pressure (P) and Saturation (S) of fluid in different places of prose media environment of the reservoir in a specific time interval. In this project we will implement a distributed reservoir simulator of a cluster. In fact parallelization of reservoir simulator is finding a method to decompose the reservoir domain into some region and assigning each region to a computer in a cluster of parallel computers in order to minimize the total amount of dependency of regions to each other and messages between nodes in the parallel network according to fluid equation in the system and finaly minimize' the duration of simulation. In this... 

Scale deposition is one of the reasons of formation damage during water injection process. This phenomenon often ocuures when two incompatible waters that interact chemically and precipitate minerals, mix within the reservoir. A typical example is sea water, with high concentration of sulfate ion and formation water, with high concentrations of calcium and/or barium ions. Mixing of these waters, therefore, can cause precipitation of calcium sulfate and/or barium sulfate. This study was conducted to investigate the permeability reduction caused by deposition of calcium and barium sulfates in carbonate cores from mixing of injected sea water and formation water in two flow rates and two... 

Upstream oil industry operators have turned to optimal production methods for further recoveries, such as smart wells. Control algorithms for smart wells must be equipped with online measurements, in other words, reflected in the feedback philosophy. On the other hand, after discretization, an oil reservoir's dynamic and control-driven model becomes a realization or a large-scale and sparse state space. One way to deal with this problem and provide an appropriate model for the design of smart well controllers is to use appropriate reservoir dimensional reduction methods. Therefore, to design low-order controllers, a study must first be performed at the level of the reservoir model and its... 

In This work, the performance of a finite volume (FV) numerical method is examined for simulating naturally fractured hydrocarbon reservoir. The dual-porosity approach applied for fracture modeling, and the flow transfer formulated based on a generalized black oil model which is based on matrix formulation, leading to a system of equations prone to degeneracy. This FV high-resolution central scheme numerical method is not sensitive to the choice of CFL number like some of other central schemes and can conveniently handle degenerate equations appearing in the reservoir simulation governing equation. In this effort, one dimension multi phase flow simulated in naturally fractured reservoir and... 

Multi-Scale finite volume (MSFV) method have been developed and applied for multiphase flow in porous media. The most important advantage of MSFV method is its computational efficiency. In this thesis we apply and implement this method to porous media simulation. Then, computational parameters such as coarsening ratio, effect of threshold on adaptive computation and different boundary conditions for computing basis functions are investigated. The two difficulties of sMSFV method are problems with high permeability contrast and problems with high course grid aspect ratio which are considered. In standard MSFV (sMSFV) method reduced boundary condition is used to determine the basis and...