SUSHIs can also be used for finite volumes

by S. Granet and O. Angélini, EDF R&D / AMA

The modelization of two-phase flows in porous media now has two new numerical schemes.

Finite volumes entered Code_Aster via the SUSHI scheme (Scheme Using Stabilisation and Hybrid Interfaces). This scheme family is efficient to represent problems of hydraulic bores (saturated environments in contact with unsaturated environments), strong contrasts, as well as to manage a phase emergence or disappearance. SUSHI is compatible with very distorted meshes.

This development was carried out within the framework of Ophélie Angélini’s thesis which was supervised by Robert Eymard, Université de Marne-La-Vallée.

The SUSHI scheme was developed for planar and 3D modelings of miscible two-phase flows. It comes in several versions: decentered line, decentered mesh, centered. Therefore 6 new modelings entered Aster:

• D_PLAN_HH2SUC (centered sushi scheme);
• D_PLAN_HH2SUDM (decentered mesh sushi scheme);
• D_PLAN_HH2SUDA (decentered line sushi scheme);
• 3D_HH2SUC (centered sushi scheme);
• 3D_HH2SUDM (decentered mesh sushi scheme);
• 3D_HH2SUDA (decentered line sushi scheme).

This figure represents the gas pressure obtained at 500 years for the modeling of a storage cell. Gas is injected in the bottom left corner during the first 500 years. Then the resaturation of the gap initially desaturated in water, and the desaturation of the geological environment initially saturated in water are observed. The gas spreads in both these two materials over time.