Techniques and Methods 6–A25
Abstract
The HYDROTHERM computer program simulates multi-phase ground-water flow and associated thermal energy transport in three dimensions. It can handle high fluid pressures, up to 1 × 109 pascals (104 atmospheres), and high temperatures, up to 1,200 degrees Celsius. This report documents the release of Version 3, which includes various additions, modifications, and corrections that have been made to the original simulator. Primary changes to the simulator include: (1) the ability to simulate unconfined ground-water flow, (2) a precipitation-recharge boundary condition, (3) a seepage-surface boundary condition at the land surface, (4) the removal of the limitation that a specified-pressure boundary also have a specified temperature, (5) a new iterative solver for the linear equations based on a generalized minimum-residual method, (6) the ability to use time- or depth-dependent functions for permeability, (7) the conversion of the program code to Fortran 90 to employ dynamic allocation of arrays, and (8) the incorporation of a graphical user interface (GUI) for input and output. The graphical user interface has been developed for defining a simulation, running the HYDROTHERM simulator interactively, and displaying the results. The combination of the graphical user interface and the HYDROTHERM simulator forms the HYDROTHERM INTERACTIVE (HTI) program. HTI can be used for two-dimensional simulations only. New features in Version 3 of the HYDROTHERM simulator have been verified using four test problems. Three problems come from the published literature and one problem was simulated by another partially saturated flow and thermal transport simulator. The test problems include: transient partially saturated vertical infiltration, transient one-dimensional horizontal infiltration, two-dimensional steady-state drainage with a seepage surface, and two-dimensional drainage with coupled heat transport. An example application to a hypothetical stratovolcano system with unconfined ground-water flow is presented in detail. It illustrates the use of HTI with the combination precipitation-recharge and seepage-surface boundary condition, and functions as a tutorial example problem for the new user. |
Version 1.0 Posted March 2008 |
Kipp, K.L., Jr., Hsieh, P.A., and Charlton, S.R., 2008, Guide to the revised ground-water flow and heat transport simulator: HYDROTHERM — Version 3: U.S. Geological Survey Techniques and Methods 6–A25, 160 p.
CONVERSION FACTORS
NOTATION
Roman Characters
Greek Characters
Mathematical Operators and Special Functions
ABSTRACT
1. OVERVIEW OF THE SIMULATOR
1.1 APPLICABILITY AND LIMITATIONS
1.2 PURPOSE AND SCOPE
1.3 ACKNOWLEDGMENTS
2. THEORY
2.1 FLOW AND TRANSPORT EQUATIONS
2.1.1 Ground-Water Flow Equation
2.1.2 Thermal-Energy Transport Equation
2.2 PROPERTY FUNCTIONS AND TRANSPORT COEFFICIENTS
2.2.1 Fluid Density Function
2.2.2 Fluid Viscosity Function
2.2.3 Temperature as a Function of Enthalpyand Pressure
2.2.4 Enthalpyand Density as a Function of Pressure and Temperature
2.2.5 Pressure-EnthalpyDiagramand the Unsaturated Zone
2.2.6 Permeability Functions
2.2.7 Relative-Per meability Functions
2.2.8 Water-Saturation Functions
2.2.9 Porous-Medium Porosity Function
2.2.10 Porous-Medium Properties as a Function of Temperature
2.3 SOURCE TERMS
2.3.1 Well Model
2.3.2 Point Sources
2.4 BOUNDARY CONDITIONS
2.4.1 Specified Pressure, Enthalpy, and Temperature Boundary Conditions
2.4.2 Specified-Flux Boundary Conditions
2.4.2.1 Precipitation-Recharge Boundary Condition
2.4.2.2 Basal Heat-Flux Boundary Condition
2.4.3 Seepage-Surface Boundary Condition
2.5 INITIAL CONDITIONS
2.6 DIMENSIONLESS NUMBERS
2.6.1 Nusselt Number
2.6.2 Thermal Peclet Number
3. NUMERICAL IMPLEMENTATION
3.1 EQUATION DISCRETIZATION
3.1.1 Spatial Discretization
3.1.2 Temporal Discretization
3.1.3 Finite-Difference Flow and Heat-Transport Equations
3.1.4 Numerical Oscillation and Dispersion Criteria
3.1.5 Automatic Time-Step Algorithm
3.1.6 Discretization Guidelines
3.2 PROPERTY FUNCTIONS AND TRANSPORT COEFFICIENTS
3.3 SOURCE TERMS
3.3.1 Well Model
3.3.2 Point Source
3.4 BOUNDARY CONDITIONS
3.4.1 Specified Pressure, Enthalpy, and Temperature Boundary Conditions
3.4.2 Specified-Flux Boundary Conditions
3.4.2.1 Precipitation-Recharge Boundary Condition
3.4.2.2 Basal Heat-Flux Boundary Condition
3.4.3 Seepage-Surface Boundary Condition
3.5 INITIAL CONDITIONS
3.6 EQUATION SOLUTION
3.6.1 Newton-Raphson Algorithm
3.6.2 Linear Equation Solution
3.6.2.1 The Slice-Successive-Overrelaxation Solver
3.6.2.2 The Generalized-Minimum Residual Solver
3.6.2.3 Equation Preconditioning
3.6.3 Choosing the Linear Equation Solver
3.6.4 Choosing the Parameters for an Iterative Equation Solver
3.6.4.1 SSOR Equation Solver
3.6.4.2 GMRES Equation Solver
3.7 GLOBAL-BALANCE CALCULATIONS
3.8 DIMENSIONLESS NUMBERS
3.8.1 Cell Nusselt Number
3.8.2 Cell Thermal Peclet Number
4. COMPUTER CODE DESCRIPTION
4.1 CODE ORGANIZATION
4.2 MEMORY ALLOCATION AND SUBPROGRAM COMMUNICATION
4.3 FILE USAGE
4.3.1 Input Files
4.3.2 Output Files
4.4 INITIALIZATION OF VARIABLES
4.5 PROGRAM EXECUTION
4.5.1 Execution of the Stand-Alone Simulator
4.5.2 Execution of the Interactive Simulator
4.6 RESTART OPTION
5. THE DATA-INPUT FILE
5.1 LIST-DIRECTED INPUT
5.2 PREPARING THE DATA-INPUT FILE
5.2.1 General Information
5.2.2 Input-Record Descriptions
6. OUTPUT DESCRIPTION
6.1 SUMMARY OF OUTPUT FILES
6.2 OUTPUT SELECTION
6.3 OUTPUT OF DATA FOR POSTPROCESSING INTO PLOTS
6.4 DIAGNOSTIC OUTPUT
7. GRAPHICAL USER INTERFACE
7.1 OVERVIEW
7.2 PREPROCESSOR
7.2.1 Pull-Down Menus
7.2.1.1 File Menu
7.2.1.2 Edit Menu
7.2.1.3 Options Menu
7.2.1.4 Show Menu
7.2.1.5 Help Menu
7.2.2 Entering and Editing Spatial Data
7.2.2.1 Domain
7.2.2.2 Rock Units
7.2.2.3 Initial Pressure
7.2.2.4 Initial Temperature
7.2.2.5 Initial Enthalpy
7.2.2.6 Boundary Conditions
7.2.2.7 Fluid Source
7.2.2.8 Observation Points
7.2.2.9 Grid
7.2.2.10 Site Map
7.3 POSTPROCESSOR
7.3.1 Pull-Down Menus
7.3.1.1 Action Menu
7.3.1.2 Options Menu
7.3.1.3 Help Menu
7.3.2 How to Run a Simulation
7.3.3 How to Replay a Simulation
7.3.4 The Postprocessor in Sand-Alone Mode
7.4 FILE MANAGEMENT
8. COMPUTER-PROGRAM CODE VERIFICATION AND EXAMPLES
8.1 SUMMARY OF VERIFICATION TEST PROBLEMS
8.1.1 Transient Vertical Infiltration in One Dimension
8.1.2 Transient Horizontal Infiltration in One Dimension
8.1.3 Two-Dimensional, Steady-State Drainage
8.1.4 Two-Dimensional, Steady-State Drainage with Thermal-Energy Transport
8.2 ADDITIONAL EXAMPLE PROBLEMS
8.3 A TUTORIAL EXAMPLE PROBLEM
9. REFERENCES CITED
APPENDIX 1 — SOFTWARE FOR HYDROTHERM AND HYDROTHERM INTERACTIVE PROGRAMS
A1.1 OBTAINING THE SOFTWARE
A1.2 INSTALLING THE SOFTWARE
A1.2.1 Distribution Layout for HYDROTHERM
A1.2.2 Distribution Layout for HYDROTHERM INTERACTIVE
A1.3 BUILDING THE SIMULATOR EXECUTABLE
APPENDIX 2 — RUNNING THE PROGRAMS
A2.1 RUNNING HYDROTHERM
A2.2 RUNNING HYDROTHERM INTERACTIVE
A2.3 RUNNING HYDROTHERM INTERACTIVE POSTPROCESSOR IN STAND-ALONE MODE
APPENDIX 3 — USER REGISTRATION