CTRAN/W

CTRAN/W Feature List

Integrated into the GeoStudio Suite

CTRAN/W is integrated into the GeoStudio suite, and therefore has access to the GeoStudio features for creating your model, analyzing it, and viewing results. CTRAN/W relies on SEEP/W to perform groundwater flow analysis required for simulating mass transport.

Comprehensive Solute and Gas Transport Formulation

CTRAN/W uses a finite element based formulation to model the movement of solutes and gases through porous materials such as soil and rock. The comprehensive formulation of CTRAN/W makes it possible to analyze problems from simple transport due to water movement, to complex processes involving diffusion, dispersion, adsorption, radioactive decay and density dependencies. CTRAN/W can be applied to the evaluation and design of geotechnical, civil, hydrogeological, and mining engineering projects.

CTRAN/W is designed to be used in tandem with a seepage analysis such as SEEP/W 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.

Typical Applications

CTRAN/W can model almost any solute or gas transport problem, including:

Flow of contaminants from a surface pond
Flow of dissolved hydrocarbons
Flow of radioactive contaminants
Gas and solute transport through fractured rock
Sea-water intrusion into coastal aquifers
Brine transport
Landfill leachate migration
Gas movement through an unsaturated mine cover

Formulated for Saturated and Unsaturated Soils

CTRAN/W is formulated for saturated and unsaturated transport, allowing the coefficient of diffusion to vary with water content and the advection process to adjust as groundwater velocities change in the unsaturated zone. In addition, CTRAN/W is capable of modelling changes in mass within a system caused by variation in water content due to processes like drainage, condensation, and vaporization.

Model Sorption and Kinematic Reactions

Solutes and gases often do not exhibit conservative behaviour while moving through soil and rock formations. Consequently, CTRAN/W is formulated to simulate many of the mechanisms contributing to this behaviour, including equilibrium sorption and first-order kinematic reactions such as radioactive decay, biodegradation, and hydrolysis.

Dual Phase Gas Transport

The gas transfer formulation gives consideration to advection and dispersion in both the gaseous and aqueous phases and includes irreversible first order reaction processes such as oxidation and decay.

Comprehensive Range of Generalized Boundary Conditions

CTRAN/W supports a comprehensive list of boundary condition options for gas and solute transport including concentration, mass rate, mass flux, source concentration, and free exit mass flux. In keeping with the entire GeoStudio suite, CTRAN/W makes broad use of generalized functions for boundary condition definition. CTRAN/W computes contaminant migration using these parameters and the advective-dispersive differential equation, derived by applying the principle of mass balance to an element of porous medium given advection, dispersion, adsorption, and decay. CTRAN/W computes adsorption using an adsorption function and the simulated nodal concentrations to determine the quantity of mass in both the fluid and solid phases.

Convenient Initial Condition Definition

The initial concentration for a transient analysis can be defined using a variety of options including a region activation concentration, spatial function, or by using the results from another CTRAN/W analysis.

Model in 1D, 2D, Axisymmetric or Plan View

CTRAN/W includes analysis options for modelling pseudo three-dimensional problems.

Powerful Graphing of Results

Graphing is critical for the interpretation of solute and gas transport analyses. The powerful graphing options in GeoStudio make it possible to plot critical information in CTRAN/W such as the spatial distribution of concentration, concentration verses time, mass fluxes, changes in mass within the domain, cumulative mass discharge, and more. All of this data can be exported or copy/pasted directly into spreadsheet software.

Sensitivity Analysis with CTRAN/W

A sensitivity analysis can be readily conducted with CTRAN/W by cloning multiple analyses using the Analysis Tree and then making slight changes to each one.

Integration with SEEP/W

CTRAN/W uses the results from a water transfer analysis as computed by SEEP/W for advection-dispersion modelling. Alternatively, CTRAN/W can be run simultaneously with SEEP/W to analyse density-dependent water flow.

Extend CTRAN/W with Add-Ins

Download and install an Add-In to enable CTRAN/W to model gas consumption due to mineral oxidation.