Study of hydraulic performance of the eddy channel for drip emitters

Clogging of emitters appears to be one of the most annoying problems related to drip irrigation. To overcome this problem, a new eddy channel replaces the traditional labyrinth channel here. The flow in the eddy channel is simulated by the computational fluid dynamics technique. The simulation results show that the pressure drop of the flow mainly exists in the cone-shaped cavities of the eddy channel, and a three-dimensional whirlpool forms in each of the cones. The velocity distribution on the radial plane of the cone shows that the flow in the cone-shaped cavities has a strong impact on the channel wall, which helps to improve the non-clogged performance of the emitter. Three structural factors are considered, and in all 40 emitters are used in the laboratory experiments. All the experimental emitters are produced by the rapid prototyping technique at low cost. The regression equations of k and x calculated with the measured discharges indicate that the cone slope is the most important factor that determines the uniformity of application of the water, and the cross-sectional area of the straight slot is the most important contributing factor to the emitter discharge. Copyright (c) 2006 John Wiley & Sons, Ltd.