Two phase flow problems in soil and rock are very important for underground structures, groundwater environment, and safety assessments of nuclear waste repository. Because of their strong non-linearity, two-phase flow problems are usually solved with numerical simulation. In our study, Mixed Hybrid Finite Element Method (MHFEM) which is considered one of the most robust methods is applied to two phase flow problems.
This paper shows general information and validation analyses of space discretization with MHFEM for two phase flow. It is shown that the number and shapes of elements give very small influence on accuracy of the results of simulations. Furthermore, too small number of elements tends to cause numerical oscillation, and it is confirmed that large Peclet number gives problems of numerical stability when pressure formulation is applied for two-phase flow.
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