Numerical methods have been proved to be useful tools for understanding different phenomena. In this paper, triggered furrow irrigation has been analyzed by means of numerical modeling. To this end, a special code is developed for simulation of triggered furrow irrigation system by coupling three-dimensional Richards’ equation and one-dimensional fully hydrodynamic form of Saint-Venant equations. The coordinate transformation technique was used for solving Richards’ equation that improves flexibility of model for simulation of water flow in irregularly shaped furrows. Furthermore, overland flow module benefits from high-resolution total variation diminishing scheme that avoids artificial oscillations commonly occurring on the advance water front. The code was validated against different analytical, numerical and experimental benchmarks. In all cases, the accuracy of model was acceptable. The code was subsequently employed to simulate all phases of triggered furrow irrigation system (including advance and redistribution phases) on a field cultivated with wheat. Finally, Taguchi technique was employed to deduct proposals to optimize performance of triggered furrow irrigation system in terms of sensor position, triggering and cutoff thresholds and inflow rate. It was concluded that optimal performance of triggered irrigation system was obtained when the water content sensor was installed close to the furrow, providing that triggering and cutoff thresholds were set as − 15 and − 3 m (close to field capacity) and inflow rate was 1 L s−1.

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