Optimizing lenght and inflow discharge in furrow irrigation

Furrow irrigation is a one of the surface irrigation in which increasing of its efficiency using optimal design and management tools were considered. In this research, a new methodology was presented to determine optimal furrow length and inlet flow rate using simulation- optimization model for three regimes including continuous, cutback and surge and evaluated using field data with clay loam texture. For evaluating of the effects of soil texture on optimization results, optimization processes were applied for sandy loam and clay soil texture. In clay loam soil, continuous regime showed longer optimal furrow length than other regimes. Surge regime needed higher inlet flow rate and shorter furrow length than other regimes to achieve maximum irrigation water efficiency and uniform distribution. Also, in continuous regime, optimal furrow length and objective function changes showed, irrigation efficiency decreases by increasing inlet flow rate. Results of objective function affects on optimal values of furrow length showed combination of application efficiency and uniform distribution and combination of tail water and deep percolation are recommended for furrow design and management.