无压灌溉土壤湿润体特征值变化规律与经验解  

The Variable Rule and Empirical Solution on Characteristic Value of Wetted Zone under Non-pressure Irrigation

作　　者：赵伟霞[1] 蔡焕杰[1] 陈新明[1] 单志杰[2] 王健[1] 

机构地区：[1]西北农林科技大学旱区农业水土工程教育部重点实验室,陕西杨凌712100 [2]中国科学院水土保持研究所,陕西杨凌712100

出　　处：《灌溉排水学报》2009年第2期30-33,共4页Journal of Irrigation and Drainage

基　　金：国家自然科学基金项目(50779059);国家863计划(2006AA100202)

摘　　要：无压灌溉土壤湿润体形状为球冠,径向和垂向最大湿润距离相等且与时间存在显著的幂函数关系,随着时间的延长,径向和垂向最大湿润距离趋于一定值。湿润体大小与供水压力之间呈抛物线关系,在零压力附近湿润体体积最大。湿润体半径与累计入渗量呈幂函数关系,拟合方程中的系数和指数为一定值,与入渗时间和供水压力无关,在试验条件下,分别为18.467和0.5037。综合以上结果,提出了预测无压灌溉土壤湿润体特征值的经验解模型。The results show that the shape of the wetted zone was spherical cap; the horizontal infiltration distance and the vertical infiltration distance was equality and had the power function relationship with time, they will tend to a fixed value when the infiltration time tend to infinity. The relationship between the wetted zone size and irrigation pressure was parabola, the maximum wetted zone volume was near the zero pressure. The relationship between the wetted radius and cumulative infiltration was power function, the coefficient and index number in fitting equation had nothing to do with the irrigation pressures, they were 18. 467 and 0. 5037 respectively under the experimental condition in this research. Synthesize the above results, the empirical solution to characteristic value of soil wetted zone under non-pressure irrigation was suggested.

关 键 词：无压灌溉 湿润体特征值 球冠 供水压力 经验解 

分 类 号：S274[农业科学—农业水土工程]