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We developed a parallel computing method of the magnetic field for rotating machines by using the 3-D finite element method (FEM) with edge elements. In this paper, we describe the outline of the developed method and an optimization of the method for the Earth simulator, which is a vector-type parallel supercomputer in Japan. Moreover, the performance of the proposed method running on the Earth simulator is quantitatively clarified. [ABSTRACT FROM AUTHOR]

Abstract: Large-scale storage of carbon dioxide in saline aquifers may cause considerable pressure perturbation and brine migration in deep rock formations, which may have a significant influence on the regional groundwater system. With the help of parallel computing techniques, we conducted a comprehensive, large-scale numerical simulation of CO2 geologic storage that predicts not only CO2 migration, but also its impact on regional groundwater flow. As a case study, a hypothetical industrial-scale CO2 injection in Tokyo Bay, which is surrounded by the most heavily industrialized area in Japan, was considered, and the impact of CO2 injection on near-surface aquifers was investigated, assuming relatively high seal-layer permeability (higher than 10 microdarcy). A regional hydrogeological model with an area of about 60km×70km around Tokyo Bay was discretized into about 10 million gridblocks. To solve the high-resolution model efficiently, we used a parallelized multiphase flow simulator TOUGH2-MP/ECO2N on a world-class high performance supercomputer in Japan, the Earth Simulator. In this simulation, CO2 was injected into a storage aquifer at about 1km depth under Tokyo Bay from 10 wells, at a total rate of 10million tons/year for 100 years. Through the model, we can examine regional groundwater pressure buildup and groundwater migration to the land surface. The results suggest that even if containment of CO2 plume is ensured, pressure buildup on the order of a few bars can occur in the shallow confined aquifers over extensive regions, including urban inlands. [Copyright &y& Elsevier]

Abstract: With the help of massively parallelized computing techniques, a comprehensive, large-scale numerical simulation of CO2 geologic storage that predicts not only CO2 migration but also its impact on regional groundwater flow was performed. As a case study, a hypothetical industrial-scale injection of CO2 at the Tokyo Bay, surrounded by the most industrialized area in Japan, was considered. In the simulation, CO2 is injected into a storage aquifer at about 1km depths under the Tokyo Bay from 10 wells with a total rate of 10 million tons/year for 100 years. A regional hydrogeological model with an area of about 60 km×70 km around the Tokyo Bay was discretized into approximately 10 million gridblocks. To solve the high-resolution model efficiently, we used a parallelized multiphase flow simulator TOUGH2-MP/ECO2N on a highest performance supercomputer in Japan, the Earth Simulator (5120 CPUs). The results suggest that even if containment of CO2 plume is ensured, pressure buildup in the order of tens of meters can occur in shallow confined layers of extensive regions including urban inlands. [Copyright &y& Elsevier]