Governing Equations and Operational Modes (e)

Like STOMP, the eSTOMP simulator has been designed with a variable source code, where source code configurations are referred to as operational modes.  Operational modes are classified according to the solved governing flow and transport equations, constitutive relation extensions, and implementation type (i.e., sequential vs. scalable).  Therefore, prior to creating an input file or assembling the source code, the user must choose the appropriate operational mode for the particular subsurface system of interest.  The selection of an operational mode requires that the user conceptualize the physical system as a computational system, which will always require making simplifying assumptions about the physical system.  The complexity and execution speed of an operational mode is generally inversely related to the number of simplifying assumptions the user can justify about the physical system.  Regardless of the operational mode complexity, the simulation of physical subsurface systems with the eSTOMP simulator always involves assumptions inherent to the founding governing equations and constitutive relations. 

The eSTOMP simulator currently has 3 operational modes, allowing the user to specify the governing equations that are to be solved.  Only the eSTOMP-W operational modes is available at this time for distribution (Applied Code), four of which are managed as safety software and comply with NQA-1 quality assurance standards. Note that options that adhere to the testing standard are marked with the NQA-1 icon on the Options pages. The remaining modes are currently restricted as research tools. Considerable attention should be given to the selection of an appropriate operational mode for the physical system of interest.  In terms of efficient and representative simulations, it is equally important not to eliminate critical physical phenomena through erroneous assumptions, as it is not to solve superfluous governing equations.  Each operational mode allows the solution of solute transport equations.  Select the Operational Mode icon below for input card descriptions specific to that mode.

Three modules are currently available as well.  Unlike STOMP, however. modules do not need to specified at compile time, rather they only need to be invoked via the input specification.  Note that not all modules are available in every operational mode.  


STATUS:    Qualified Code  Research Code Applied Code

MODULES:   Reactive Transport   Barrier   Radioactive Decay




Solved Coupled





Available in


Water mass


Water mass
Air mass




Water mass

CO2 mass

Salt mass


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