中文摘要：

通过室内试验分析了管长、滴头间距和入口压力3个因素对滴灌管总水头损失的影响，结果表明：滴灌管总水头损失随管长和首部压力的增大、滴头间距的减小而增大，且变化速率随管长增大和滴头间距减小而增大，随首部压力的变化较为稳定，呈现良好的线性相关关系。针对目前滴灌管水力计算需要推求多孔系数、估算扩大系数、计算量大等问题，将影响滴灌管水头损失的基本量滴灌管入口断面平均流速00、滴灌管内径D、液体动力黏滞系数v、重力加速度g、为管道长度三、滴头间距s，运用量纲分析方法导出为四个无量纲量v0D／v，v0^2／gD，LD／s^2和ε，通过多元回归建立了具有量纲和谐性的滴灌管水头损失计算公式，分析了滴灌管能坡曲线的函数形式，回归得到了水头损失比和沿程压力分布模型。以上模型预测值与实测数据拟合效果良好，可为滴灌系统水力计算及设计提供参考。

英文摘要：

The effects of pipe length, emitter spacing and operating pressure of drip irrigation laterals on their total head loss were studied in this work using laboratory tests. The results showed that the total head loss was increased with inlet pressure or pipe length, but decreased with emitter spacing. Of these three factors, the variation in head losses caused by inlet pressure took the mildest trend. In the complicated calculation procedure of a drip lateral, six physical parameters were considered： mean inlet velocity 00, drip lateral diameter D, pipe length L, emitter spacing s, kinematic viscosity of water v, and gravitational acceleration g. We have developed a multiple regression model using four dimensionless variables of roD~v, o02/gD, LD/s2 and e （contraction ratio of the emitter installation section） for prediction of head loss. By this model, we derived a formula for calculation of the energy loss and formulated a method to determine the pressure at any location along the drip lateral through analysis of the corresponding energy gradient. The predicted values agree well with the experimental measurements. Our results would help hydraulic design and evaluation of drip irrigation systems.