The design and hydraulic performance studies of a Tesla valve‐type drip irrigation emitter

Abstract

The Tesla valve‐type drip irrigation emitter is a novel type of drip irrigation emitter that allows one‐way fluid flow and sharp water flow diversion. Orthogonal test schemes were employed to analyse the impact of structural parameters and energy dissipation mechanisms on hydraulic performance. The effect of vortex partitioning in forward and reverse flow channels on hydraulic performance was analysed. A prediction model for the emitter discharge exponent (flow index) of the structural parameters was established. The results indicated that the emitter discharge exponents of forward‐Tesla valve‐type drip irrigation emitters (FTEs) ranged from 0.47 to 0.506, and those of reverse‐Tesla valve‐type drip irrigation emitters (RTEs) ranged from 0.51 to 0.533. There was a significant disparity in the distribution of vortex zones between the FTE and RTE. The local loss coefficients of the FTE were 2.12–10.84, and those of the RTE were 1.00–3.71. The channel width D had a substantial impact on the emitter discharge exponents of the FTE and RTE, whereas the inlet length of diverter K, the length of the bevelled edge of raindrop‐type diverter B and the opening angle of raindrop‐type diverter θ had relatively smaller effects on the emitter discharge exponent. The determination coefficients of the regression model for the FTE and RTE were 0.89 and 0.84, respectively. The relative errors between the simulated and estimated values were −4.57% to 1.21%, and the experimental and estimated values were −3.72% to −1.45% in the FTE. The relative errors between the simulated and estimated values were −0.98% to 2.86%, and the experimental and estimated values were −3.72% to 1.45% in the RTE. These relative errors were all under 5%, indicating that the estimation of the emitter discharge exponent can be more accurate.