| In this paper,the 1828 button-type pressure-compensated irrigator produced by Huawei Water Saving Technology Group Co.,Ltd.is taken as the experimental research object;the annular labyrinth flow channel in the irr igator is numerically simulated by CFD-DEM coupling,and the numerical simulation analysis of different flow rates,different concentrations,Pressure distribution,flow velocity distribution and particle motion of annular labyrinth flow channel under diff erent particle sizes.Using the button-type pressure compensation irrigator as the test piece,the hydraulic performance of 8 kinds of inlet pressures（50～350k Pa）and the anti-clogging performance of 3 kinds of muddy water with different concentrations（3.0,5.0 and7.0g/L）were tested.And the particle size in the LDPE pipe and the irrigator was measured by the Omega laser particle sizer LS-CWM（3）.The main conclusions are as follows:（1）For the button-type pressure compensation sprinkler,the hydraulic performance test under 8 kinds of inlet pressures（50～350k Pa）shows that the average flow rate of the sprinkler does not change with the increase of pressure,and the outflow rate is basically stable.This is due to the joint action of the rubber shrapnel and the labyrinth flow channel structure of the button-type pressure compensation irrigation device.The uniformity is high and the pressure compensation is strong.The compensation range is 110-350k Pa,the average flow rate is 2.115L/h,the coefficient of variation is 0.07,and the standard deviation of the flow rate is 0.07.0.16,flow coefficient 2.05,deviation rate 0.06,flow index 0.006.All conform to GB/T 19812.2-2017 Plastic water-saving irrigation equipment,pressure-compensated dripper and drip irrigation pipe.The pressure-flow relationship is obtained as（?）=2.05（?）0.006.（2）In order to reduce energy consumption,a suitable inlet pressure can be selected during the test;there is a slow water area in the middle area of the runner,which is easy to produce blockage;there is a small vortex at the tail end of the runner at t=0.5seconds at the inlet speed of 0.25m/s,and the inlet concentration and the distribution position of the particles inside the runner have a great influence.（3）The higher the muddy water concentration,the less irrigation times.With the increase of irrigation times,the clogging rate of the irrigator increased.After 40irrigations,the clogging rate of the irrigator reached 20.8,29.2 and 52.1%,respectivel y.The muddy water concentration had a great influence on the clogging of the irrigator.When the concentration of sediment is 5.0g/L and 7.0g/L,the blockage rate increases significantly,and when the sediment concentration is 3.0g/L and below,the anti-clogging performance is good,The use time was 29.73%and 41.89%longer than that at 5.0 and 7.0 g/L,respectively.（4）The small particle size is mainly accumulated in the LDPE pipe,which causes the blockage of the irrigation device mainly due to the lar ge particle size and the small particles and fine hairs（linear fibers in the tap water）still attached to the flow channel in the water.The particle size of the fine particles in the LDPE pipe keeps making random motions with the water flow,and continuo usly hits the suspended particles randomly.When the concentration was 3.0g/L,D10,D50 and D90 decreased by 56.4,51.54 and 48.48%compared with the concentration of 7.0g/L,respectively. |
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