HYDRUS-1D Tutorial Example 2
Inverse Problem - One-Step Outflow Method
Project Manager
Button "New"
Name: Onestep
Description: Onestep Outflow Method
Button "OK"
Main Processes
Heading: Onestep Outflow Method
Check "Inverse Solution"
Inverse Solution
Check "Soil Hydraulic Parameters"
Check "No Internal Weighting"
Max. Number of Iteration: 20
Number of Data Points: 10
Geometry Information
Number of Soil Materials: 2
Number of Layers for Mass Balances: 2
Depth of the Soil Profile: 4.52
Time Information
Time Units: Hours
Final time: 100
Initial Time Step: 0.001
Minimum Time Step: 0.0001
Maximum Time Step: 10
Print Information
Uncheck "Screen Output"
Number of Print Times: 10
Button "Select Print Times":
0.017
0.033
0.05
0.167
0.5
1.33
5.417
10
15
100
Water Flow - Iteration Criteria
Upper Limit of the Tension Interval: 15000
Water Flow - Soil Hydraulic Model
Water Flow - Soil Hydraulic Parameters
Initial Estimate:
qr =0.15
qs =0.388
a=0.025
n=1.5
Ks =5.4
l= 0.5
Fitted: qr ,a,n
Second Material:
qr =0
qs =1
a=1e-20
n=1.001
Ks =0.003
l= 0.5
Water Flow - Boundary Conditions
Upper Boundary Condition: Constant Flux
Lower Boundary Condition: Constant Pressure Head
Water Flow - Constant BC
Data for Inverse Solution
0.017
-0.07860
0
2
1
0.033
-0.16160
0
2
1
0.05
-0.20970
0
2
1
0.167
-0.34080
0
2
1
0.5
-0.44560
0
2
1
1.033
-0.4980
0
2
1
2.75
-0.56140
0
2
1
5.417
-0.59370
0
2
1
100
-0.68240
0
2
1
-15000
0.157
5
1
1
Soil Profile - Graphical Editor
Menu: Options -> Grid - Height: 0.05
Menu: Condition -> Profile Discretization
Button "Number": 50
Button "Insert Fixed" at 3.95 cm
Button "Density": deselect "Use upper", upper density =0.1 at 3.95 cm
Menu: Condition -> Initial Condition -> Pressure Head
Button "Edit condition"
Select entire profile:
Top value=-2
Bottom value=2.52
Deselect "Use top value for both"
Lowest node = -1000 cm
Menu: Condition -> Material Distribution
Button "Edit condition"
Select the ceramic plate and specify "Material Index"=2
Ditto for "subregions"
Observation Points?
Soil Profile - Summary
Execute HYDRUS
OUTPUT:
Water Flow - Boundary Fluxes and Heads
Soil Hydraulic Properties
Inverse Solution Information
