内镶贴片式滴灌带局部水头损失试验研究  

Experimental study on local head loss in thin-wall drip irrigation pipes with non-coaxial emitters

作　　者：王剑[1] 魏涛 杨婷[1] 袁寿其[1] WANG Jian;WEI Tao;YANG Ting;YUAN Shouqi(National Research Center of Pumps,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏大学国家水泵及系统工程技术研究中心

出　　处：《排灌机械工程学报》2019年第12期1100-1104,共5页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(51709130);中国博士后科学基金资助项目(2017M621653)

摘　　要：通过试验研究了标准管径16 mm的5种内镶贴片式滴灌带的局部水头损失,分析了滴灌带局部水头损失占沿程水头损失的比值hjt/hf和局部水头损失系数α的变化规律.结果表明:相同工作压力下,滴灌带当量直径随壁厚的增大而减小,造成沿程水头损失和局部水头损失的增大,局部水头损失与壁厚、滴头断面面积和雷诺数有关.随着雷诺数的增大,滴灌带局部水头损失占沿程水头损失的比值hjt/hf减小,最小值可达到0. 67,但仍超过中国制定的微灌工程技术规范设计标准(0. 1~0. 2).通过对试验数据进行多元回归分析,提出了滴灌带局部水头损失系数与过水断面收缩比和雷诺数的关系式,相关系数为0. 96.The local head loss of non-coaxial emitters in five thin-wall drip irrigation pipes with standard diameter of 16 mm was studied by conducting hydrodynamic experiment. The variation of the ratio of local head loss to friction head loss along the drip irrigation pipe,hjt/hf,and the local head loss coefficient α,were analyzed. The results show that under the same working pressure,the equivalent diameter of drip irrigation pipe decreases with the increase of wall thickness,resulting in the increase of friction head loss and local head loss along the drip irrigation pipe. The local head loss is related to wall thickness,emitter cross section area and Reynolds number. With the increase of Reynolds number,the ratio of local head loss to friction head loss along the drip irrigation pipe( hjt/hf,) decreases.The mi-nimum value reaches 0. 67,but it still exceeds the design standard of China’s technical specification for micro-irrigation engineering( 0. 1-0. 2). Based on the multiple regression analysis of the test data,the relationship between the local head loss coefficient and the contraction ratio of cross section and Rey-nolds number is proposed,and the correlation coefficient is 0. 96.

关 键 词：滴灌 滴灌带 局部水头损失 局部水头损失系数 

分 类 号：S275.6[农业科学—农业水土工程]