Zero-Inertia Modeling of Furrow Irrigation Advance

The rate of advance of the water front in furrows has been mathematically modeled using a zero-inertia approach, in which the surface water hydraulics are simplified by neglecting accelerations. Power curve relationships are used to relate both the flow depth and wetted perimeter to the cross-sectional flow area. Infiltration is described with the modified Kostiakov equation, which has a constant term that accounts for a soil's basic intake rate. Field evaluations from three Colorado farms were used in testing the model. It was shown that the zero-inertia model can effectively simulate the hydraulics of the advance phase of furrow irrigation.