Development of a New Parallel Thermal Reservoir Simulator
Abstract
Thermal reservoir simulation is the most complex of all reservoir simulators and thus the most computationally intensive. With the advent of computer science, today's commodity PC clusters consist of a large number of discrete computer processors distributed across a network. Improving robustness and performance of parallel reservoir simulators on new high performance computing architectures remains a key issue to address. New numerical difficulties and performance problems appear because computing architecture is very sensible to memory distribution and load balance. This project proposes a new domain partition algorithm based on a fully-distributed graph framework. A reservoir is divided into multiple subregions, where connections, defined by geometry and well perforation information, are weighted by transmissibility and well indices. The continuity of fluxes and better load balance are guaranteed.
Different strategies with different message passing frequency and accuracy are proposed for high performance computation. The subregion coupling effects are released or distracted into a linear system according to the physical principles. Subregions are coupled dramatically at flooding fronts and high frequency phase-changing regions, which enhances messages passing through processors. An analytical Jacobian calculation method and a variable alignment scheme are developed in this thesis. They have the ability to simulate three-dimensional multi-component three-phase thermal processes, and are capable of determining different property estimation approaches, such as correlations or table interpolations. An automatic time step algorithm, different variable-ordering algorithms and a Gauss elimination technique are implemented to reduce the intensive computation of linear iterations and to speedup the simulation process.
The simulator is validated by analytical and numerical experiments, which include the Buckley-Leverett problem and the fourth SPE comparative solution project. The capability of this simulator is demonstrated through cyclic steam stimulation, steam flooding and steam-assisted gravity drainage processes. Three different parallelism strategies are tested in this thesis. A highly scalability implementation is achieved. This efficient, accurate, and parallel thermal simulator is applicable to highly complex reservoir systems.
Description
Keywords
Engineering--Petroleum
Citation
Zhong, H. (2016). Development of a New Parallel Thermal Reservoir Simulator (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/25665