土壤中吸附性溶质运移对流-弥散模型的准解析解及其数值模拟  

Quasi-analytical solution and numerical simulation for advection-dispersion model of adsorbed solute transport through soils under steady state flow

作　　者：张德生[1] 常安定[2] 沈冰[1] 武新乾[1] 

机构地区：[1]西安理工大学,西安710048 [2]长安大学,西安710054

出　　处：《水动力学研究与进展（A辑）》2005年第2期226-232,共7页Chinese Journal of Hydrodynamics

基　　金：国家自然科学基金资助项目(59879022);西安理工大学科技创新项目(108 210301)

摘　　要：给出了稳定流条件下,同时考虑随深度变化的一阶降解和随深度变化的线性平衡吸附时,一维溶质运移的对流 弥散方程。在初始浓度为零,半无限一维空间内定通量边界条件下,推导出了溶质相对浓度的准解析表达式。用特征有限元法建立了相应的数值模型,从数值解和准解析解的计算数据可以看出:数值计算所产生的误差很小,能满足实际工作对计算精度的要求。The advection-dispersion model of 1-D solute transport through soils with depth-dependent first-order degradation and depth-dependent linear equilibrium sorption under steady state flow is studied, and a quasi-analytical solution describing the concentration distribution is deduced under the initial zero concentration and the constant flux boundary condition of a semi-infinite 1-D space. The numerical model of the advection-dispersion model is constructed by the characteristic finite element method. It can be seen from comparing the numerical solutions to the quasi-analytical solutions that the errors caused by the numerical computation are so small that the numerical model perfectly meets the demand of the calculation precision in practical work.

关 键 词：对流-弥散方程 吸附 降解 准解析解 特征有限元法 

分 类 号：S153.5[农业科学—土壤学]