Tutorial 3.01
Infiltration into a one-dimensional soil profile
The first example represents infiltration into a one-meter deep loamy soil profile. In this example we use the internal structural mesh generator to construct a one-dimensional profile using two vertical columns each discretized into 51 nodes. Infiltration is run for one day. Ponded infiltration is initiated with a zero pressure head at the soil surface, while free drainage is used at the bottom of the soil profile. The example is divided into two parts: (A) first, only water flow is considered, after which solute transport is added. Solute transport is evaluated for both (B) Dirichlet and (C) Cauchy upper boundary conditions. Users in this example become familiar with most dialog windows of the main module, and with the use of the internal structural mesh generator.
- Water flow
- Solute transport with third-type (Cauchy) upper boundary condition
- Possible modifications
1. Infiltration of Water Into a One-Dimensional Soil Profile
Video (24 MB) - Download
Download Project Infiltr1.zip (0,2 MB) Project Manager (File->Project Manager)
Button “New”
New Project (or File->New Project)
Name: Infiltr1
Description: One-Dimensional Infiltration of Water Into Soil Profile
Working Directory: Temporary – is deleted after closing the project
Button “Next”
Geometry Information (Edit->Domain Geometry->Geometry Information)
Type of Geometry: 2D Vertical Plane
Domain Definition: Rectangular
Units: cm
Initial Workspace: Not important when working with rectangular or hexahedral geometry
Button “Next”
Rectangular Domain Geometry (Edit->Domain Geometry->Geometry Definition)
Dimension Lx: 1 cm
Dimension Lz: 100 cm
Slope: 0
Button “Next”
Main Processes (Edit->Flow and Transport Parameters->Main Processes)
Check Box: Water Flow
Button “Next”
Time Information (Edit->Flow and Transport Parameters->Time Information)
Time Units: days
Final Time: 1
Initial Time Step: 0.0001
Minimum Time Step: 0.00001
Maximum Time Step: 1
Button “Next”
Output Information (Edit->Flow and Transport Parameters->Output Information)
Print Options:
Check T-Level Information
Check Screen Output
Check Press Enter at the End
Print Times: Count: 10
Update
Button “Next”
Water Flow - Iteration Criteria (Edit->Flow and Transport Parameters->Water Flow Parameters->Output Information)
Leave default values as follows:
Maximum Number of Iterations: 10
Water Content Tolerance: 0.001
Pressure Head Tolerance: 1
Lower Optimal Iteration Range: 3
Upper Optimal Iteration Range: 7
Lower Time Step Multiplication Factor: 1.3
Upper Time Step Multiplication Factor: 0.7
Lower Limit of the Tension Interval: 0.0001
Upper Limit of the Tension Interval: 10000
Initial Condition: In the Pressure Head
Button “Next”
Water Flow - Soil Hydraulic Model (Edit->Flow and Transport Parameters->Water Flow Parameters ->Soil Hydraulic Model)
Radio button - van Genuchten-Mualem
Radio button - No hysteresis
Button “Next”
Water Flow - Soil Hydraulic Parameters (Edit->Flow and Transport Parameters->Water Flow Parameters ->Soil Hydraulic Parameters)
Leave default values for loam
Explore Catalog of Soil Hydraulic Properties and Neural Network Predictions
Button “Next”
FE-Mesh - FE-Mesh Generator (Edit->FE-Mesh->FE-Mesh Generator)
Radio button - Structured
Button “Next”
FE-Mesh - FE-Mesh Parameters (Edit->FE-Mesh->FE-Mesh Parameters)
Horizontal Discretization in X-direction: Count = 2, Update
Vertical Discretization in Z-direction: Count = 51, Update
Explore the meaning of terms in the Generate Vertical Coordinates
Button “Next”
Default Domain Properties (Edit->Domain Properties->Default Domain Properties)
Change the value of the pressure head (h) to 0 cm
Button “Next”
Toolbar – View All (View->View All) to display the entire profile in the View window.
View->View Stretching
Stretching Factors, In the X-direction: 20 (to adjust the display in the View window)
Boundary Condition – Water Flow (from Navigator Bar):
Constant Head from the Edit Bar (or Insert->Boundary Conditions->Water Flow->Constant Head.
Select two nodes at the soil surface, Specify h=0 cm.
Free Drainage from the Edit Bar (or Insert->Boundary Conditions->Water Flow-> Free Drainage.
Select two nodes at the bottom of the soil profile.
Domain Properties - Observation Nodes (from the Navigator Bar):
Button “Insert” from the Edit Bar (or Insert->Domain Properties->Observation Nodes)
Select nodes at z-coordinates of 20, 40, 60, 80, 100 cm one side of the soil column (note that coordinates are displayed in the right bottom corner). Inserted observation nodes are displayed in the list on the Edit Bar.
Menu: File->Save (or from Toolbar)
Menu: Calculation->Run HYDRUS (or from Toolbar) OUTPUT:
Results – Other Information: Observation Points (from the Navigator Bar, or Results->Observation Points from menu)
Pressure Heads
Water Contents
Results – Other Information: Boundary Fluxes (from the Navigator Bar, or Results->Boundary Information->Boundary Fluxes from menu)
Constant Boundary Flux
Free Drainage Boundary Flux
Results – Other Information: Cumulative Fluxes (from the Navigator Bar, or Results->Boundary Information->Cumulative Fluxes from menu)
Constant Boundary Flux+ Free Drainage Boundary Flux
Results – Other Information: Mass Balance Information (from the Navigator Bar, or Results->Mass Balance Information from menu)
Results – Graphical Display: Pressure Heads (from the Navigator Bar, or Results->Display Quantity->Pressure Heads from menu)
Use Listbox Time Layer or Slidebar on the Edit Bar to view results for different print times
Check Flow Animation
Select Boundary Line Chart from the Edit Bar and draw pressure heads for one vertical column
Select Cross Section Chart and draw pressure heads through the middle of the column
Select different display modes using Options->Graph Type
Results – Graphical Display: Water Contents (from the Navigator Bar, or Results->Display Quantity->Water Contents from menu)
Results – Graphical Display: Velocity Vectors (from the Navigator Bar, or Results->Display Quantity->Velocity Vectors from menu)
2. Infiltration of Water and Solute Into a One-Dimensional Soil Profile
Video (12 MB) - Download
Download Project Infiltr2.zip (0,2 MB)
Close the Infiltr1 Project (click Save Project at the Toolbar or File->Save)
Project Manager (File->Project Manager)
Select the Infiltr1 project
Button “Copy”
Name: Infiltr2
Description: One-Dimensional Infiltration of Water and Solute Into Soil Profile
Button “OK”
Main Processes (Edit->Flow and Transport Parameters->Main Processes)
Check Box: Solute Transport
Button “OK”
Solute Transport – General Info (Edit->Flow and Transport Parameters->Solute Transport Parameters->General Information)
Leave default values
Button “Next”
Solute Transport - Solute Transport Parameters
Leave the default values
Bulk Density = 1.5 cm3/g
Disp.L = 0.5 cm
Disp.T = 0.1 cm
Diff.=0
Button “Next”
Solute Transport - Transport Parameters
Leave the default values for tracer
Note that cBnd in Boundary Conditions is equal to 1 (this is boundary concentration)
Button “Next”
Boundary Condition – Solute Transport (from Navigator Bar):
Note that Cauchy Boundary Conditions is applied by default
Menu: File->Save (or from Toolbar)
Menu: Calculation->Run HYDRUS (or from Toolbar) OUTPUT:
Results – Other Information: Observation Points (from the Navigator Bar, or Results->Observation Points from menu)
Concentrations
Results – Other Information: Solute Fluxes (from the Navigator Bar, or Results->Boundary Information->Solute Fluxes from menu)
Constant Boundary Flux
Seepage Face Boundary Flux
Results – Other Information: Mass Balance Information (from the Navigator Bar, or Results->Mass Balance Information from menu)
Results – Graphical Display: Concentrations (from the Navigator Bar, or Results->Display Quantity->Concentrations from menu)
Use Listbox Time Layer or Slidebar on the Edit Bar to view results for different print times
Check Flow Animation
Select Boundary Line Chart from the Edit Bar and draw pressure heads for one vertical column
Select Cross Section Chart and draw pressure heads through the middle of the column
Select different display modes using Options->Graph Type
3. Possible Modifications
Video (24 MB) - Download
Download Project Infiltr3.zip (0,2 MB)
Two Soil Horizons
Close the Infiltr2 Project (click Save Project at the Toolbar or File->Save)
Project Manager (File->Project Manager)
Select the Infiltr1 project
Button “Copy”
Name: Infiltr3
Description: One-Dimensional Infiltration of Water and Solute Into Layered Soil Profile
Button “OK”
Time Information (Edit->Flow and Transport Parameters->Time Information)
Final Time: 5 (flow will be slower since the upper layer is silt)
Button “Next”
Output Information (Edit->Flow and Transport Parameters->Output Information)
Print Options:
Default
Button “Next”
Water Flow - Soil Hydraulic Parameters (Edit->Flow and Transport Parameters->Water Flow Parameters ->Soil Hydraulic Parameters)
Number of Materials: 2, Update
Select First Line
From the Catalog of Soil Hydraulic Properties select Silt
Button “OK”
Domain Properties – Material Distribution (from the Navigator Bar):
On the Edit Bar, Click on Material 2
And assign it to the bottom 50 m of the column
Menu: File->Save (or from Toolbar)
Menu: Calculation->Run HYDRUS (or from Toolbar) OUTPUT:
Results – Other Information: Observation Points (from the Navigator Bar, or Results->Observation Points from menu)
Results – Graphical Display: Concentrations(from the Navigator Bar, or Results->Display Quantity->Concentrations from menu)