It is of great scientific significance to reveal the flow characteristics of dentiform emitters and to optimize the channel structure of emitters to improve the anti-clogging properties of emitters, which contribute to improving the working performance of irrigation systems. The study was carried out using computational fluid dynamics (CFD) simulations, combined with the physical test in the laboratory. First, this paper analyzes the distributions of flow velocity, kinetic energy in turbulence, and physical particle trajectories inside the different structural emitters based on CFD simulations, and based on the simulation results, a dentiform emitter optimization scheme was proposed, and two-channel structures, including the structurally improved emitter, were arranged to conduct indoor tests for verification. The result shows that the maximum kinetic energy in turbulence in the flow channel appeared in the main flow area and that the area of strongest energy dissipation in turbulence was at the tooth tip. The main flow area was largest for the emitter with the triangular channel, and the turbulence energy of the low-speed region was highest for the circular trapezoidal structure. The results suggested a scheme for further optimization of the dentiform emitter. For the optimized channel structure, the maximum value of turbulent kinetic energy was increased by about 19-101% compared with the other four flow channels. The area of the main flow region and the kinetic energy in turbulence in the low-speed area in the emitter were increased. In addition, the range of kinetic energy in turbulence was increased by 52-200% in the low-speed region of the channel. The transport rate of physical particles was increased, and the transport distance and residence time of the particles were reduced. The physical test results show that the optimized channel structure emitter achieved a decrease in the clogging probability compared with the other four structures. Therefore, increasing the area of the main flow region and the low-speed area in the flow channel is an effective physical way of physically improving the anti-clogging performance of the emitter.
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