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本文讨论了含裂隙介质地下水污染物输运与生物降解非线性方程组数值求解方法．方程含有对流项、扩散项、生长、死亡、吸附、解吸、趋化和孔隙与裂隙介质界面间的交换项的非线性偶合，使算法十分困难．本文讨论了无生化过程时的几种求解方法，数值结果表明：用三次迎风插值法对常见的对流项占优势，且场变量有较大梯度的问题较适用．在讨论有生化反应过程时，利用对流项与生化反应项的特征时间量级估算，给出了求生化过程作用子步的时间步长估算办法．用上述方法所得到的模拟结果与解析解、无化学反应和有化学反应的实测值对比，吻合很好．
This paper discusses the numerical solution method of nonlinear equations for the transport and biodegradation of groundwater pollutants in fractured media. The equations contain convective terms, diffusion terms, growth, death, adsorption, desorption, chemotaxis and nonlinear coupling of the exchange terms between pore and fracture media interfaces, making the algorithm very difficult. In this paper, we discuss several methods of solving non-biochemical processes. The numerical results show that it is more suitable to use the three-way upwind method to dominate the common convection term and the larger gradient of field variables. In discussing the process of biochemical reaction, the time step of estimating the substeps of biochemical process is given based on the characteristic temporal order estimation of convection term and biochemical reaction term. The simulation results obtained by the above method are in good agreement with the analytic solutions, without chemical reaction and with the measured values of the chemical reaction.