摘要
为提高微孔渗灌条件下土壤水分运动数值模拟精度,建立了含有第3类边界条件的二维微孔渗灌土壤水分运动数学模型,着重论述了微孔管3类边界条件处理的流速分解法,并采用ADI交替方向隐式差分法求解数学模型。室内试验结果表明,在渗灌管边界,模拟计算结果的相对误差在6.7%以内,远离渗灌管的地方误差更小,实测值与模拟值二者吻合较好。说明建立的数学模型、边界条件和求解方法具有较高的精度,提出的微孔管边界处理的流速分解法具有可行性,可用来模拟各种因素(微孔管特性、供水特性与土壤特性)影响下微孔渗灌条件下的土壤水分运动。
In order to acquire more accuracy of numerical simulation of soil water movement under subsurface irrigation with porous pipe, a two dimension soil-water movement model with boundary of third type was built in this paper. And flow rate resolution method which applies to dealing with third type boundary of porous pipe was expounded explicitly. Alternative direction implicit technique （ADI） is used to solve this model. Experiment was done indoor. Results of test show that the measurement value and the evalua- tion one are identical well. And the relative error of evaluation value is less than 6.7 near the boundary of porous pipe. At the same time, with increase of length from porous pipe, the errors become smaller more and more. Comparison shows that the model built in this paper, the boundary and the solution method have high precision. And the flow rate resolution method is feasible. The model can be used to simulate soil moisture dynamics under subsurface irrigation with the effects of porous pipe properties, water head in pipe and soil parameters.
出处
《灌溉排水学报》
CSCD
北大核心
2008年第4期37-40,共4页
Journal of Irrigation and Drainage
基金
沈阳农业大学青年教师科研基金(2005057)
关键词
渗灌
土壤水分运动
数值模拟
交替方向隐式差分
流速分解法
subsurface irrigation
soil-water movement
numerical simulation
alternative direction implic-it
flow rate resolution
