摘要
【目的】利用改进无单元Galerkin法求解非线性Poisson-Boltzmann方程。【方法】将改进的移动最小二乘近似与非线性Poisson-Boltzmann方程的Galerkin弱形式耦合,建立了非线性Poisson-Boltzmann方程的改进无单元Galerkin法。基于改进移动最小二乘近似的误差结果下,推导了非线性Poisson-Boltzmann方程的改进无单元Galerkin法的误差估计。【结果】在Sobolev空间中获得了误差估计,并通过数值算例验证了理论结果。【结论】该方法具有较高的计算精度和较好的稳定性,误差随节点间距的减小而降低。
[Purposes]The nonlinear Poisson-Boltzmann equation is solved and analyzed by the improved element-free Galerkin method.[Methods]Combining the improved moving least square approximation with Galerkin weak form,the improved element-free Galerkin method is establish for the nonlinear Poisson-Boltzmann equation.Based on the error results of the improved moving least square approximation,the error of the improved element-free Galerkin method for nonlinear Poisson-Boltzmann equation is derived theoretically.[Findings]Error estimation is obtained in the Sobolev space.Numerical examples verify the theoretical analysis.[Conclusions]The method has higher calculation accuracy and better stability.The errors decrease as the nodal spacing reduces.
引文
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