1 / 28

Density-Dependent Flows

Density-Dependent Flows. Primary source: User’s Guide to SEAWAT: A Computer Program for Simulation of Three-Dimensional Variable-Density Ground-Water Flow By Weixing Guo and Christian D. Langevin U.S. Geological Survey

clydes
Download Presentation

Density-Dependent Flows

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Density-Dependent Flows Primary source: User’s Guide to SEAWAT: A Computer Program for Simulation of Three-Dimensional Variable-Density Ground-Water Flow By Weixing Guo and Christian D. Langevin U.S. Geological Survey Techniques of Water-Resources Investigations 6-A7, Tallahassee, Florida2002

  2. Sources of density variation • Solute concentration • Pressure • Temperature

  3. USGS • HST3D • Three-dimensional flow, heat, and solute transport model • HYDROTHERM • Three-dimensional finite-difference model to simulate multiphase ground-water flow and heat transport in the temperature range of 0 to 1,200 degrees Celsius • MOCDENSE • Temperature is assumed to be constant, but fluid density and viscosity are assumed to be a linear function of the first specified solute. • SEAWAT and SEAWAT-2000 • A computer program for simulation of three-dimensional variable-density ground water flow • SHARP • A quasi-three-dimensional, numerical finite-difference model to simulate freshwater and saltwater flow separated by a sharp interface in layered coastal aquifer systems • SUTRA and related programs • 2D, 3D, variable-density, variably-saturated flow, solute or energy transport

  4. Others • 3DFATMIC • 3-D transient and/or steady-state density-dependent flow field and transient and/or steady-state distribution of a substrate, a nutrient, an aerobic electron acceptor (e.g., the oxygen), an anaerobic electron acceptor (e.g., the nitrate), and three types of microbes in a three-dimensional domain of subsurface media. • 3DFEMFAT • 3-D finite-element flow and transport through saturated-unsaturated media. Combined sequential flow and transport, or coupled density-dependent flow and transport. Completely eliminates numerical oscillation due to advection terms, can be applied to mesh Peclet numbers ranging from 0 to infinity, can use a very large time step size to greatly reduce numerical diffusion, and hybrid Lagrangian-Eulerian finite-element approach is always superior to and will never be worse than its corresponding upstream finite-element or finite-difference method. • FEFLOW • FEFLOW (Finite Element subsurface FLOW system) saturated and unsaturated conditions.  FEFLOW is a finite element simulation system which includes interactive graphics, a GIS interface, data regionalization and visualization tools. FEFLOW provides tools for building the finite element mesh, assigning model properties and boundary conditions, running the simulation, and visualizing the results. • FEMWATER • 3D finite element, saturated / unsaturated, density driven flow and transport model • SWICHA (old) • three-dimensional finite element code for analyzing seawater intrusion in coastal aquifers. The model simulates variable density fluid flow and solute transport processes in fully-saturated porous media. It can solve the flow and transport equations independently or concurrently in the same computer run. Transport mechanisms considered include: advection, hydrodynamic dispersion, absorption, and first-order decay. • TARGET (old) • 3D vertically oriented (cross section), variably saturated, density coupled, transient ground-water flow, and solute transport (TARGET-2DU); • 3D saturated, density coupled, transient ground-water flow, and solute transport (TARGET-3DS).

  5. Freshwater Head • SEAWAT is based on the concept of equivalent freshwater head in a saline ground-water environment • Piezometer A contains freshwater • Piezometer B contains water identical to that present in the saline aquifer • The height of the water level in piezometer A is the freshwater head

  6. Converting between:

  7. Mass Balance • (with sink term)

  8. Product Rule

  9. Density • Chain rule (and soon T!)

  10. Water Compressibility

  11. Medium Compressibility

  12. Specific storage • Volume of water per unit change in pressure:

  13. Densities • Freshwater: 1000 kg m-3 • Seawater: 1025 kg m-3 • Freshwater: 0 mg L-1 • Seawater: 35,000 mg L-1

  14. Flow Equation

  15. Darcy’s law

  16. CDE

  17. Program Flow

  18. Benchmark Problems • Box problems (Voss and Souza, 1987) • Henry problem (Voss and Souza, 1987) • Elder problem (Voss and Souza, 1987) • HYDROCOIN problem (Konikow and others, 1997)

  19. Henry Problem

  20. Henry

  21. Hydrocoin

  22. L Salt Source E Heater Elder Problem C=0 E/H=4 L/H=2 Temperature-induced buoyancy Solute-induced buoyancy H C=1 Elder, J. W. (1967) J. Fluid Mech. 27 (3) 609-623 Voss, C. I., W. R. Souza (1987) Wat. Resour. Res. 23, 1851-1866

  23. Elder Problem L C=1 H C=0 E // Controlling parameter Elder, J. W. (1967) J. Fluid Mech. 27 (3), 609-623

  24. Elder Problem L C=1 H C=0 E // Controlling parameter Elder, J. W. (1967) J. Fluid Mech. 27 (3), 609-623

  25. Results Thorne & Sukop (2004) Elder (1967) Year 1 Year 2 60% 20% Year 4 Year 10 60% 60% 20% 20% Year 15 Year 20 20% 60% 20% 60% • Notes • No fully accepted results (computer or lab). • Maybe no unique solution. Elder, J. W. (1967) J. Fluid Mech. 27 (1), 29-48 Elder, J. W. (1967) J. Fluid Mech. 27 (3), 609-623 Woods, J. A., et al. (2003) Wat. Resour. Res. 39, 1158-1169

  26. Results Thorne & Sukop (2004) Frolkovič & De Schepper (2001) Thorne & Sukop 80% Year 1 60% Year 2 80% 40% 60% 40% 20% 20% Year 4 Year 10 80% 80% 60% 60% 40% 20% 40% 20% Year 15 Year 20 80% 80% 80% 80% 60% 60% 40% 40% 20% 20% Frolkovič, P., H. De Schepper (2001) Adv. Wat. Res. 24, 63-72

  27. Results (year 15) Thorne & Sukop (2004) Thorne & Sukop (2004) Elder (1967) Frolkovič & De Schepper (2001) Thorne & Sukop Year 15 20% 60% Year 15 80% 80% 80% 60% 40% 20%

More Related