Validation of the new B2B Bankless Channel Irrigation System model
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Validation of the new B2B Bankless Channel Irrigation System model Michael Grabham , R. Soppe, J. Hornbuckle, R. Smith and S. Raine
description
Validation of the new B2B Bankless Channel Irrigation System model. Michael Grabham , R. Soppe, J. Hornbuckle, R. Smith and S. Raine. Outline. System overview Hydraulic challenges B2B model Bay-scale comparison Whole field simulations Conclusions. System Overview. System overview. - PowerPoint PPT Presentation
Transcript of Validation of the new B2B Bankless Channel Irrigation System model
Validation of the new B2B Bankless Channel Irrigation System model
Michael Grabham, R. Soppe, J. Hornbuckle, R. Smith and S. Raine
Outline
System overview Hydraulic challenges B2B model Bay-scale comparison Whole field simulations Conclusions
System Overview
System overview
System overview
Why the system is being considered
Advantages– Labour savings– Can be automated– Machine efficiency– Expanded cropping options
Hydraulic challenges
Hydraulic challenges
Variable inflow rates Variable bay sizes Bay to bay hydraulic interaction
Time
Flow
rate
Hydraulic challenges
Variable bay sizes– 60:100:40 bay ratios– Surface storage volume
accumulation– Interconnecting pipe size
selection– Drainage water minimisation
Hydraulic challenges
Hydraulic challenges
Hydraulic challenges
Hydraulic challenges
Bay to bay hydraulic interaction– Calculate the available
volumes– Calculate inflow rates– Select adequate bay
dimensions– Select adequate pipe sizes
B2B model
B2B model
Current simulation models– Single dimension– Variable inflow– Recession phase limitations– Assume free flowing drainage
B2B model
Clemmens’ (2007) surface irrigation design approach– Volume balance principles– Spreadsheet based– Simultaneously solves for
advance and inlet depth– Uses fixed inflow
B2B model
Darcy Weisbach equation
B2B model
Clemmens’ ApproachClemmens’ Approach
Darcy Weisbach equation
Bay scale comparison
B2B – Bay Scale Discharge
Errors from MeasuredwinSRFR = 65%SISCO = 65%
B2B = 18%
B2B – Bay Scale Advance and recession
B2B – Bay Scale Infiltrated depth
B2B – Bay Scale Simulation discrepancies
– Attributed to model assumptions1. Level water surface2. Friction ignored3. Infiltration during recession
Field simulations
B2B – Field Scale Advance and recession
Bay 1
Bay 2
Bay 3
B2B – Field Scale
Depth
B2B – Field Scale
Inlet hydrographs
B2B – Field Scale
Inlet cumulative hydrographs
Conclusions
Novel approach taking into account bay-to-bay interaction
Enables simulation of multiple bay systems Discrepancies with known causes
Acknowledgements
CRC IF Postgraduate scholarship IAL and CRC IF Travel Fund grant CSIRO Land and Water, Griffith USQ, Toowoomba
Acknowledgements
