Integrated into the GeoStudio Suite

AIR/W is integrated into the GeoStudio suite, and therefore has access to the GeoStudio features for creating your model, analyzing it, and viewing results.

Comprehensive Air Flow Formulation

AIR/W is a finite element CAD software product for analyzing air flow or air-groundwater interaction problems within porous materials such as soil and rock. Its comprehensive formulation allows you to consider analyses ranging from single phase steady-state problems to sophisticated dual phase time-dependent problems. AIR/W can be applied to the analysis and design of geotechnical, civil, hydrogeological, and mining engineering projects.

Typical Applications

AIR/W can model geotechnical problems including:

• Simple single phase air flow problems
• Density dependent air flow that contributes to convective heat transfer in freezing / thawing soils (when coupled with TEMP/W)
• Soil vapor extraction systems
• Evaluation of tunnel air pressure for water inflow control
• Air and water pressure response ahead of water infiltration fronts
• Movement of gases through porous media (when coupled with CTRAN/W)

Formulated for Single Phase or Dual Phase Flow

Air transfer analysis can be conducted using a single phase or dual phase material model. Single phase air transfer means that only pressure and gravity-driven air flow is considered, while storage changes occur due solely to pressure changes. The dual phase material model integrates with SEEP/W to allow air conductivity and storage changes to be linked to changes in water content.

Estimate Material Properties from Measured Data

The air conductivity function can be generated based on the dry soil air conductivity and a user-selected volumetric water content function. The estimation process requires only fundamental information such as soil classification or grain size distribution.

Comprehensive Range of Generalized Boundary Conditions

AIR/W supports a comprehensive list of boundary condition options including pore-air pressure, pore-air total head, flux rate, and flow rate. In keeping with the entire GeoStudio suite, AIR/W makes use of either constants or generalized functions for boundary condition definition. As such, actual field data or user-specified functional relationships can be pasted into AIR/W to define boundary conditions.

Model Barometric Air Pressure at the Ground Surface

Modeling air transfer in porous media, such a convective air flow in a waste rock dump, requires careful consideration of the air pressure conditions at the ground surface. The barometric air pressure boundary condition computes the pressure based on the absolute pore-air pressure and air temperature conditions, along with a reference elevation, according to the Barometric Formula.

Integrate with TEMP/W to model Diverse Problem Sets

AIR/W can be combined with TEMP/W to model free-convection (density-driven) air transfer. Integration of AIR/W and TEMP/W also allows for the simulation of heat transfer via forced-convection.

Convenient Initial Condition Definition

Initial conditions for transient analyses can be determined using a variety of options including a spatial function of pore-air pressure, activation pore-air pressure, or results from another GeoStudio finite element analysis.

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

AIR/W includes analysis options for modeling pseudo three-dimensional problems such as air permeameter field tests or coupled-air water radial flow to a well.

Powerful Graphing of Results

Graphing is critical for the interpretation of an air flow system. The powerful graphing options in GeoStudio make it possible to plot critical information in AIR/W such as pore-air pressure profiles, air flow versus time, and material properties. All of this data can be exported or copy/pasted directly into spreadsheet software.

Visualize Air Flow Paths

Once the analysis is complete, you can interactively click on any part of the domain to visualize the air flow path through this point.

Sensitivity Analysis with AIR/W

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

Optimization and Calibration

AIR/W can be paired with other software to conduct optimization/calibration of material properties.