Development of a New Parallel In-Situ Combustion Simulator
Creators: name: He, Ruijian
Publisher: name: Graduate Studies
Year: 2018
Subjects: subject: Engineering
subject: Engineering--Petroleum

description: As a competitive recovery method for heavy oil, In-Situ Combustion (ISC) shows its great potential accompanied by technological advances in recent years. Reservoir simulation will play an indispensable role in the prediction of the implementation of ISC projects. With the computational complexity, it is imperative to develop an effective and robust parallel in-situ combustion simulator. First of all, a mathematical model for In Situ Combustion is proposed. The model takes full consideration for related physical phenomena, including multi-dimensional multicomponent three-phase flow, heat convection and conduction, chemical reactions, and mass transfer between phases. In the mathematical model, different governing equations and constraints are involved, forming a complicated PDE (partial differential equation) system. For physical and chemical behaviors, some special treatments for the ISC simulator are discussed and applied. Also, a modified PER (Pseudo-Equilibrium Ratio) method is proposed in the thesis. To solve the PDE system, a fully implicit scheme is applied, and discretization is implemented with the FDM (Finite Difference Method). In solving nonlinear systems, the Newton Method is introduced, and both numerical and analytical Jacobian matrices are applied. Due to the complexity of an ISC problem, an appropriate decoupling method must be considered. Thus the Gauss-Jordan transformation is raised. Then, with certain preconditioners and iterative solvers, a numerical solution can be obtained. For the treatment of a thin combustion front, a direct idea is to apply a fine grid to an ISC model. However, the scale of a numerical problem will increase significantly. The approach ii given in this thesis is parallelization. Because of their outstanding characteristics, clusters are considered to be the platform of the simulator. Communications and synchronizations are deemed to be the significant factors that affect the parallelization. A dynamic load balancing grid partitioning method, HSFC, is applied for this purpose. The results of different models are given, which are validated with the results from CMG STARS. Also, the scalability of parallelization is proved, indicating the excellent performance of parallel computing. This accurate, efficient, parallel ISC simulator applies to complex reservoir modelse significantly. The approach given in this thesis is parallelization. Because of their outstanding characteristics, clusters are considered to be the platform of the simulator. Communications and synchronizations are deemed to be the significant factors that affect the parallelization. A dynamic load balancing grid partitioning method, HSFC, is applied for this purpose. The results of different models are given, which are validated with the results from CMG STARS. Also, the scalability of parallelization is proved, indicating the excellent performance of parallel computing. This accurate, efficient, parallel ISC simulator applies to complex reservoir models.