Abstract：In order to improve the irrigation uniformity of low pressure drip irrigation system, a jet-pulse tee generator was invented based on the attachment and switching principle. Effects of pulse frequency and amplitude on irrigation uniformity coefficient and flow rate deviation ratio were studied experimentally under various pressures conditions, and the influence of lateral pipe length and inlet pressure on irrigation uniformity coefficient was also analysed in pulse conditions. Results show that the irrigation uniformity coefficient of jet-pulse tee is 0.65 % higher than the ordinary tee in average and its mean deviation ratio is obviously lower than that of the ordinary tee, exhibiting a decrease by 3.62% in average. In addition, under low pressure conditions, the pulse frequency generated by the tee is higher than 200 times/min and the pulse amplitude is larger than 2.5 m. At an identical pressure, the irrigation uniformity coefficient decreases with increasing length of lateral pipe, but the flow rate deviation ratio increases considerably with the length. In the same length, the flow rate through the emitter increases with increasing inlet pressure, and so does the inlet flow rate. In a word, the pulse leteral pipe is only concerned. However, the irrigation uniformity of a pulse branch and a pulse irrigation area will be tackled in the future. Nevertheless, this will extend drip irrigation equipment, and is an effective way to create a high-performance drip irrigation system.
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