Hydrodyn-STMSOFT

It is an absolute user friendly system, developed specifically for environmental engineers, who may not have much exposure to numerical concepts in data creation , calculation and analysis.

What is STMSOFT?

Hydrodyn-STMSOFT is an advanced computer program used to simulate ground-water flow and associated heat and solute transport in three dimensions. It can be used for analysis of problems such as those related to sub-surface waste injection, landfill leaching, saltwater intrusion, freshwater recharge and recovery, radioactive-waste disposal, hot-water geothermal systems, and subsurface-energy storage. The three governing equations of flow, solute and heat transport are coupled through the interstitial pore velocity, the dependence of the fluid density and fluid viscosity on pressure, temperature, and solute-mass fraction and solved them using stable finite difference techniques. The software is also having options to define source and sink to represent complex well flows.

Hydrodyn-STMSOFT includes many specialized features of graphics and menu driven pre/postprocessor facilities for setting up the input, running the calculation selecting and obtaining graphical output from the analysis. It allows fast, flexible creation and modification of computational models, while greatly reducing the possibility of errors in the input. It is available for UNIX workstations and windows environment.

Features

• Solves saturated ground-water flow equation, heat-transport equation and the solute- transport equation, which may decay and may adsorb onto the porous medium.


• Specified-value and specific-flux boundary conditions are independent on each portion of the boundary and may vary with time.


• Specified heat and solute flux boundary conditions are available.


• Leakage, aquifer-influence function river leakage, and evapotranspiration boundary conditions are available.


• Porous media thermal properties, dispersivity and compressibility may have spatial variation defined by zones.


• A point-distributed, finite-difference grid is used rather than a cell or block-centered grid. It allows a better truncation error and an easy incorporation of boundary conditions.


• The heat conduction boundary condition is generalized to apply to any cell face.


• Global flow, heat and solute balance calculations are performed including flux calculations through specified pressure, temperature and mass fraction boundaries.


• A robust algorithm for the computation of the optimum over-relaxation factor for the two-line successive over-relaxation matrix solution method is employed with a convergence criterion that includes the matrix spectral radius estimate.


• A read-echo file is written. It assists the user in locating errors in the data-input file. Although the internal calculations of the program are performed in metric units, the input and output can be chosen to be in inch-pound units. Error tests are included to locate mistakes in data input. Error messages are printed explicitly rather than as code numbers. The solute concentration can be chosen to be the mass fraction or a scaled mass fraction that ranges from 0 to 1.


• Map-contours of any output or input data may be created directly on the screen.


• Initial pressure conditions can be specified to be other than hydrostatic. For example, an initial water-table configuration can be used.


• Precipitation and replenishment can be specified using the distributed flux-boundary conditions.


• The conductive heat loss to overburden and underburden is a general heat transfer calculation, applicable to any cell face in the region.


• The well-riser calculation has been formulated to solve the total energy and momentum balance equations simultaneously using the Bulirsh-Stoer algorithms for integration of the ordinary differential equations.


• Well bore equations in STMSOFT are implicitly coupled to the system equations for cases of cylindrical geometry.


• The well-datum pressure and the well flow rate calculations may be performed explicitly or iteratively in conjunction with the solution of the flow equation.


• The full nine components or an approximate three-component dispersion coefficient tensor may be used for cross-dispersive flux calculations.


• The user can select the boundary conditions at any location and select any type of boundary conditions i.e. steady or transient.


• A graphical interface i.e. pre-processor is integrated to the model to define the required model input graphically.


• Various objects, i.e. zones, head boundaries and various pre-processor objects are represented by different colors to identify the objects easily.


• Multi view point dynamic post-processing facilities for output results.


• The solver has options for flow and solute transport calculations i.e. direct and iterative.


• The monitor points can be selected at any location in the computational domain to monitor the output results and show the results graphically.


• It displays help menu whenever the user calls for it.

Application Areas

• Assess well performance including the type of well bore.
• Analyze pressure flow, heat and solute transport in the saturated zone with variable or constant density and viscosity.
• Model ground-water flow separately.
• Model heat and/or solute transport coupled with ground-water flow.
• Predict chemical species transport including landfill contaminant movement.
• Predict waste injection into saline aquifers.
• Analyze freshwater storage in saline aquifers and saltwater intrusion in coastal aquifers.
• Analyze liquid-phase geothermal systems and heat storage in aquifers.
• Model brine disposal and movement of connate water.
• Model contaminant (single species) transport in complex 3D aquifer systems.
• Model hydraulic barriers, liners and water-quality protection systems.
• STMSOFT include the study of waste injection into fresh and saline aquifers, contaminant plume movement, sea-water intrusion in coastal regions, brine disposal, freshwater storage in saline aquifers, heat storage in aquifers, liquid-phase geothermal systems, and similar transport situations.