Abstract:Based on the structures of impact sprinkler PY30, a gas suction pipe was inserted in the middle position of the sprinkler tube to form an aeration impact sprinkler. As the fixed and rotating impact sprinkler works at the low pressure, the gas-liquid two-phase jet spray could improve the hydraulic performance of the sprinkler. With the same flow rate at the working pressure of 100 kPa, 200 kPa and 300 kPa respectively, impact sprinklers with or without aeration were comparatively studied. Experiments were carried out to study the sprinkler hydraulic parameters affected by the gas-liquid jet and the variation of gas flow rate, including the water distribution in the radial direction, the ranges of jet and so on. At the same time, the combination uniformity coefficient in different distance was calculated for square arrangement mode. The results showed that at the same working pressure and flow rate, PY30 impact sprinkler and its aeration impact sprinkler had nearly the same jet range. With re-ference to the outlet of sprinkler nozzle, the gas suction pipe moved from-1.5 mm to 0 mm and 2.0 mm, the vacuum of gas suction pipe increased gradually and the amount of gas flow rate q became larger. In the meantime, the water distribution of the impact sprinkler was compared with that of the aeration impact sprinkler, the precipitation in the middle range of sprinkler water jet was enhanced gra-dually and the peak tended to the interval values. At the working pressure of 200 kPa and 300 kPa, the optimum combination distance of the aeration impact sprinkler is R and the combination uniformity coefficients of the sprinkler irrigation are 2.5% and 1.9% greater than those of the impact sprinkler.
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