### CTRAN/W 污染物擴散分析軟體

CTRAN/W is a finite element software product that can be used to model the movement of contaminants through porous materials such as soil and rock. The comprehensive formulation of CTRAN/W makes it possible to analyze problems varying from simple particle tracking in response to the movement of water, to complex processes involving diffusion, dispersion, adsorption, radioactive decay and density dependencies. You can apply CTRAN/W to the analysis and design of geotechnical, civil, hydrogeological, and mining engineering projects.

CTRAN/W is integrated with SEEP/W and has the same CAD-like interface. The two software products must be used in tandem to analyze contaminant transport. SEEP/W computes the water flow velocity, volumetric water content, and water flux. CTRAN/W uses these parameters to compute the contaminant migration.

**Defining a Contaminant Transport Model**

Once you have solved your flow problem with SEEP/W, you can use the graphical tools in CTRAN/W to interactively apply boundary conditions and specify material properties. Conduct a simple particle tracking analysis, or define dispersivity, diffusion, adsorption, decay and density to conduct an advection-dispersion analysis. If you make a mistake, you can correct it using the Undo command.

**Viewing the Analysis Results**

Once you have solved your contaminant transport problem, CTRAN/W offers many tools for viewing results. Generate contours or x-y plots of any computed parameter, such as concentration, mass, adsorption, dispersion, or Peclet and Courant numbers. Velocity vectors show the flow direction and rate. Examine the contaminant mass in the solid and liquid phases at any location. Transient conditions can be shown by plotting the changing concentration levels over time. Interactively query computed values by clicking on any node, element Gauss region, or flux section. Then export the results into other applications, such as Microsoft Excel or Word, for further analysis or to prepare presentations.

CTRAN/W can model almost any contaminant transport problem, including:

- Flow of contaminants from a surface pond
- Flow of dissolved hydrocarbons
- Flow of radioactive contaminants
- Transport through fractured rock
- Sea-water intrusion into coastal aquifers
- Brine transport
- Landfill leachate migration