The focus of our research is the migration of fluids in porous media. Results of this work have included the following:


1

Development of a numerical simulation for gas-water, non-aqueous-phase-liquid (NAPL), three-phase flow with a dusty gas model.

We developed, in particular, a method for numerically simulating gas-water-NAPL, three-phase flow and the migration of a chemical substance in a porous medium. The gas-water-NAPL, three-phase flow simulation employs a modified Picard iteration and finite element methodology. We have applied the dusty gas model in the case of multiple components to the migration of a chemical substance in the gas phase of a porous medium. Finally, in our laboratory we have integrated the dusty gas model with the gas-water-NAPL, three-phase flow simulation and developed the following simulation program (anwflowDGM written in fortran):
Simulator name anwflowDGM

References

  • Hibi, Y., Nakata, S., Sugiyama, A., 2010. Estimation of effects on NAPL residual saturation for air-water-NAPL phase flow in porous media. Journal of Geotechnical Engineering Japan Society and Civil Engineers. 66(2), pp. 418–429 (in Japanese).
  • Hibi, Y., Fujinawa, K., Nishizaki, S., Okamura K., Tasaki, M., 2009. Multi-component migration in the gas phase of soil: Comparison between results of experiments and simulation by Dusty Gas Model. Soils and Foundations 49(4), 569–582.
  • Hibi, Y., 2008. Formulation of a dusty gas model for multi-component diffusion in the phase of soil. Soils and Foundations 48(3), 419–432.
  • Hibi, Y., Fujinawa, K., 2005. A comparison of numerical model for air-water-NAPL three-phase flow in porous media. Journal of Geotechnical Engineering Japan Society and Civil Engineers. 797/VII, pp. 81–94 (in Japanese).
  • Hibi, Y., Fujinawa, K., Fujiwara, Y., 2001. A comparison of finite element solution for pressure based and mixed type equations of two-phase flow in porous media, In International Association for Research Committee on Groundwater Hydraulics 1st Groundwater Seminar between China, Korea and Japan International Association for Hydraulic Research, Fukuoka, pp. 41–52.
2

Development of a method for obtaining Knudsen coefficients and diffusion coefficients with tortuosity and mechanical dispersion.

Determination of the Knudsen coefficient and diffusion coefficient with tortuosity and mechanical dispersion requires simulation with the dusty gas model. We developed a method for obtaining these parameters by using column experiments and an inverse simulation program as follows:
Inverse simulator name invgasflow

References

  • Hibi, Y., Kanou, Y., Ohira, Y., 2012. Estimation of mechanical dispersion and dispersivity in a soil-gas system by column experiments and dusty gas model. Journal of Contaminant Hydrology 131, pp. 39–53.
  • Kanou, Y., Hibi, Y., Ohira, Y., 2012. Valuation of parameters for migration of components in the gas system obtained by using column experiments, Journal of Geotechnical Engineering Japan Society and Civil Engineers 68(1), pp. 57–67 (in Japanese).
  • Hibi, Y., Taguchi, T., 2011. Development of a method to estimate the dispersion and Knudsen diffusion coefficients in soil by using the dusty gas model. Journal of Geotechnical Engineering Japan Society and Civil Engineers 67(2), 198–204 (in Japanese).
3

Current study

At the moment we are developing a numerical simulation method for coupling surface water and groundwater systems. This numerical simulation employs a one-field model for multiple immiscible fluids to simulate gas-liquid, two-phase flow of surface water and takes into account effects of atmospheric circulation. The flow of groundwater is modeled with a water-saturation formulation.