泥沙质量浓度和工作压力对不同结构微喷带抗堵塞性能的影响

针对含沙水灌溉时微喷带堵塞的问题,采用间歇微喷灌的试验方法,选取泥沙质量浓度、工作压力和微喷带结构为试验因素,以平均相对流量、孔组流量均匀度和孔组流量降幅为微喷带堵塞程度评价指标,分析微喷带的堵塞状况和易堵塞的位置,研究工作压力和含沙水的泥沙质量浓度对微喷带堵塞的影响过程及机制。结果表明：1)4种微喷带(带宽分别为45、45、48和60 mm,单循环孔组孔数分别为3、5、5和5孔)中,带宽为45 mm的2种微喷带的堵塞程度较轻,单循环孔组孔数为5孔的微喷带,用最大的泥沙质量浓度1.5 g/L灌水时,平均相对流量最低仅为清水流量的87.14%～96.19%;2)工作压力为30和40 kPa时,微喷带易出现全面堵塞;而当工作压力为50和60 kPa时,微喷带多为局部堵塞;3)10次灌水结束后,微喷带堵塞最严重的部位多发生在尾部,其次是首部。综上,4种微喷带中带宽45 mm,单循环孔组孔数为5孔的微喷带抗堵塞性能最优,微喷带的工作压力和含沙水的泥沙质量浓度交互作用共同影响微喷带的堵塞程度,使用不同泥沙质量浓度的水源灌溉时应合理选用工作压力。

Effects of sediment mass concentration and working pressure on the anti-clogging performance of micro-sprinkling hoses with different structures

The test method of intermittent micro-sprinkling irrigation was used to address the problem of micro-sprinkling hose blockage during irrigation with sandy water. Sediment mass concentration, working pressure and micro-sprinkling hose structure were selected as the test factors, average relative flow, flow uniformity of orifice group and flow drop of orifice group were used as the evaluation indexes of the clogging degree of the micro-sprinkling hose. The blockage condition and the position of the micro-sprinkling hose were analyzed, and the influence process and mechanism of the working pressure and the sediment mass concentration of the sandy water on the blockage of the micro-sprinkling were studied. The results show that: 1)Among the four types of micro-sprinkling hoses(the folded diameter of 45, 45, 48 and 60 mm, respectively; and the number of orifices in the single circulating orifice group of 3, 5, 5 and 5, respectively), the clogging degree of two types of micro-sprinkling hoses with the folded diameter of 45 mm was relatively light, while the maximum sediment mass concentration of 1. 5 g/L, the average relative flow rate of the micro-sprinkling hose with the single circulating orifice group of 5 orifices was only 87. 14% to 96. 19% of that of clear water. 2)When the working pressure was 30 and 40 kPa, the micro-sprinkling hoses were prone to full blockage. When the working pressure was 50 and 60 kPa, the micro-sprinkling hoses were mostly blocked locally. 3)After 10 times of irrigation, the most serious part of the micro-sprinkling hose blockage occurred in the tail, followed by the head. In summary, among the four types of micro-sprinkling hoses, the micro-sprinkling hose with the folded diameter of 45 mm and a single circulating orifice group of 5 orifices had the best anti-clogging performance. The interaction between the working pressure of the micro-sprinkling hose and the sediment mass concentration of the sandy water affected the blockage degree of the micro-sprinkling hose. The working pressure should be reasonably selected when using different sediment mass concentration water sources for irrigation.