期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
一个浅水波方程的Semi—Lagrangian—半隐式格式试验方案
1
作者 卢敬华 赵邦杰 《成都信息工程学院学报》 1989年第2期14-25,共12页
在正形投影坐标系下,半拉格朗日法与半隐式法相结合积分浅水波方程导出的模式,用一小时的时间步长,是无条件稳定。我们作了一个60小时的实例时间积分,计算稳定。半隐式积分格式导致求解一个赫姆霍茨方程,为比较其高低精度的优劣,我们提... 在正形投影坐标系下,半拉格朗日法与半隐式法相结合积分浅水波方程导出的模式,用一小时的时间步长,是无条件稳定。我们作了一个60小时的实例时间积分,计算稳定。半隐式积分格式导致求解一个赫姆霍茨方程,为比较其高低精度的优劣,我们提出在空间上用二阶精度和四阶精度解赫姆霍茨方程的超松驰法,同时,作了有无地形的试验。应该注意列,半拉格朗日法含有大量的插值,因而,在每一步时间步长里此积分格式比通常的欧拉法含有更多的计算,但是每一时间步长的计算量的增加却从使用很大的时间步长得到了更多的补偿。 展开更多
关键词 数值天气预报 半拉格朗日法 半隐式法 浅水波方程
下载PDF
Error Estimate for Semi-implicit Method of Sphere-Constrained High-Index Saddle Dynamics
2
作者 Lei ZHANG Pingwen ZHANG Xiangcheng ZHENG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2023年第5期765-780,共16页
The authors prove error estimates for the semi-implicit numerical scheme of sphere-constrained high-index saddle dynamics,which serves as a powerful instrument in finding saddle points and constructing the solution la... The authors prove error estimates for the semi-implicit numerical scheme of sphere-constrained high-index saddle dynamics,which serves as a powerful instrument in finding saddle points and constructing the solution landscapes of constrained systems on the high-dimensional sphere.Due to the semi-implicit treatment and the novel computational procedure,the orthonormality of numerical solutions at each time step could not be fully employed to simplify the derivations,and the computations of the state variable and directional vectors are coupled with the retraction,the vector transport and the orthonormalization procedure,which significantly complicates the analysis.They address these issues to prove error estimates for the proposed semi-implicit scheme and then carry out numerical experiments to substantiate the theoretical findings. 展开更多
关键词 Saddle point Constrained saddle dynamics Solution landscape semiimplicit Numerical analysis
原文传递
A VERTICAL 2D MATHEMATICAL MODEL FOR HYDRODYNAMIC FLOWS WITH FREE SURFACE IN σ COORDINATE 被引量:15
3
作者 ZHANG Jing-xin LIU Hua XUE Lei-ping 《Journal of Hydrodynamics》 SCIE EI CSCD 2006年第1期82-90,共9页
Numerical models with hydrostatic pressure have been widely utilized in studying flows in rivers, estuaries and coastal areas. The hydrostatic assumption is valid for the large-scale surface flows where the vertical a... Numerical models with hydrostatic pressure have been widely utilized in studying flows in rivers, estuaries and coastal areas. The hydrostatic assumption is valid for the large-scale surface flows where the vertical acceleration can be ignored, but for some particular cases the hydrodynamic pressure is important. In this paper, a vertical 2t) mathematical model with non-hydrostatic pressure was implemented in the σ coordinate. A fractional step method was used to enable the pressure to be decomposed into hydrostatic and hydrodynamic components and the predictor-corrector approach was applied to integration in time domain. Finally, several computational cases were studied to validate the importance of contributions of the hydrodynamic pressure. 展开更多
关键词 vertical 2D model free surface flow semiimplicit NON-HYDROSTATIC
原文传递
THE FORMULATION OF A PERFECT SQUARE CONSERVATIVE SEMI-IMPLICIT TIME DIFFERENCE SCHEME AND ITS PRELIMINARY CHECK 被引量:3
4
作者 钟青 《Chinese Science Bulletin》 SCIE EI CAS 1992年第6期497-502,共6页
Quantitative studies of scientific problems require solving correspondent mathematical models. Although a great deal of mathematical models of evolutional problems are set up under continuous space-time meaning, they ... Quantitative studies of scientific problems require solving correspondent mathematical models. Although a great deal of mathematical models of evolutional problems are set up under continuous space-time meaning, they usually had to be solved numerically after space-time discretization because nonlinear mathematical models except some 展开更多
关键词 nonlinear SEMI-IMPLICIT perfecr SQUARE CONSERVATIVE time difference scheme COMPUTATIONAL finstability COMPUTATIONAL accuracy
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部