Numerical Modeling and Analysis of Drainage Patterns of Saltcake in a Column

Saltcake, previously dissolved salts, such as sodium nitrate and sodium nitrite that crystallize out of solution, is a kind of porous media and an important component in many nuclear waste tanks. In this paper both one-dimensional single-phase and multi-phase flow model was employed to simulate unsaturated drainage of saltcake in a column caused by gravity or external forces under given initial and boundary conditions. Porous media properties used in the modeling was determined from our previous experimental data by inverse modeling method. Good agreement was found between the drainage result from available experiments and that from the numerical simulation using multiphase flow model. The impact on drainage by external pressure applying at the top of column and the influence of the height of column were also be investigated and presented in this study.