水力驱动式比例施肥器性能影响因素试验研究

Experimental Research on the Influencing Factors of Performance of Hydraulic Driven Proportional Fertilizer

水力驱动式比例施肥器具有施肥精度高,运行稳定的优点,在滴灌系统中使用越来越普遍。为了达到设计要求的灌溉均匀度,滴灌系统毛管首部压力应不低于设计压力,在保持滴灌带首部压力不变的前提下,进行了水力驱动式比例施肥器的性能试验,分析了吸肥泵作用压差、施肥比例、吸肥比例对吸肥量及管道内肥液浓度的影响。结果表明:在设计流量范围内,施肥泵入口流量随作用压差的增大呈现先增后减的趋势,施肥比例对入口流量基本没有影响,在压差0.02~0.035 MPa时运行性能较稳定;同一压差下,吸肥比例的实测值与设定值的偏差随着吸肥比例的增加而增大,同一吸肥比例的条件下,施肥泵出口和汇入干管后肥液的质量百分浓度基本不随时间变化,随着施肥桶中的肥液浓度的增加而增加,反映出比例施肥泵均匀性高的特点。为了提高施肥精度,在运行时不要使用较大压差与较小施肥比例配合以及较小压差与较大施肥比例配合。

Proportional water-driven fertilizer applicator has the advantages of high fertilization accuracy and stable operation,and is more and more widely used in the drip irrigation system. In order to achieve the irrigation uniformity required by the design,the head pressure of the drip irrigation system should not be less than design pressure. In this study,the performance of the hydraulically driven proportional fertilizer is tested and the effect is analyzed by keeping the head pressure unchanged The amount of fat absorption of the various factors. The results show that the flow rate at the inlet of fertilizer pump increases first and then decreases with the increase in differential pressure within the range of designed flow rate. The proportion of fertilization does not affect the inlet flow rate basically. When the pressure difference is0.02 ~ 0.035 MPa,the operation performance is stable. Difference between the measured value of the proportion of suction and the deviation of the set value increases with the increase in the proportion of suction,with the same ratio of absorption of fertilizer,fertilizer pump outlet and after the import of the quality of the liquid pipette after the percentage concentration does not basically change with time,with the increase in fertilizers in the barrels of fertilizer concentration increases,reflecting the proportion of fertilization pump characteristics of high uniformity. In order to improve fertilization accuracy,it is not advisable to use a larger pressure drop and a smaller proportion of fertilizers at run time,as well as a smaller pressure drop and a larger proportion of fertilizers.