Abstract：In view of poor spray uniformity and short range in low-pressure sprinklers, various special-shaped nozzles are designed based on a principle of identical cross-sectional area. Then ANASY CFX is applied to simulate three-dimensional internal flow field in these sprinklers. The numerical simulation results are validated by using the measured performance parameters of low-pressure sprinklers, including range, water distribution and raindrop diameter. The simulated results show that the region occupied by high velocity at the outlet of inverted U shaped nozzle is the largest and the velocity profile keeps consistent with increasing working pressure, showing a very good advantage in extending the range and improving the spray uniformity. The experimental results show that the range of inverted U shaped nozzle is about 1.110 times that of the circular nozzle, which is basically around 2% lower than the prediction. At a 300 kPa working pressure, the drop diameter generated by the inverted U shaped nozzle is 4.21 mm as the minimum, showing the best atomization performance. The water distribution in that nozzle is approximately triangular, all the uniformity coefficients are more than 82%. With increasing distance, the water through the circular and rounded rectangular nozzles rises first, and then decreases, and all their uniformity coefficients are lower than the inverted U shaped nozzle. In conclusion, the hydraulic performance of the inverted U shaped nozzle is better in comparison with the others, particularly, the range is increased on the basis of uniformity improved.
张前, 袁寿其, 刘俊萍, 鲍亚. 低压喷头喷嘴优化设计及内部流场数值模拟[J]. 排灌机械工程学报, 2016, 34(5): 449-454.
ZHANG Qian, YUAN Shouqi, LIU Junping, BAO Ya. Optimization design of nozzle and numerical simulation of internal flow field in low-pressure sprinkler. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(5): 449-454.
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