Iterative-dynamic-reduction

水下机器人在线最小二乘辨识、应急导航策略研究(Recursive Identification of Autonomous Underwater Vehicle for Emergency Navigation)

该文件解决了电磁场和天线问题计算当中的近远场转换的问题，它也可以应用在一般散射问题的求解中。(this file contains an algorithm that could solve problems within the EM and antenna near to far field questions. Also, it could be used in general scattering problems.)

用LBM结合非平衡外推方法实现的圆柱绕流，柱面边界以非平衡外推方法实现。(LBM combined with the extrapolation method of achieving non-equilibrium flow around a cylinder, cylinder boundary to achieve non-equilibrium extrapolation method.)

可以对高温状态下的混凝土材料进行准确的塑型模型构建(It can be used to construct accurate plastic model of concrete under high temperature)

说明：  该蠕变子程序能够进行高温长时间应力下的应力应变分析以及松弛行为(The creep subroutine can be used for stress-strain analysis and relaxation behavior under high temperature and long time stress)

ABAQUS中用户材料子程序UMAT的开发主要解决两方面的问题：本构模型的建立和积分算法的选择。 本文主要研究非线性材料的UMAT实现方法，并重点研究其迭代算法部分，目前，用户材料子程序UMAT的迭代算法主要是常刚度法，常刚度法的优点在于算法原理较简单，程序编写较方便，缺点是当遇到复杂非线性材料时，其迭代次数较多，收敛速度也较慢，在这个情况下，本文采取的是一种迭代次数较少且收敛速度较快的切线刚度法，具体就是采用FORTRAN语言编制了基于Von-Mises模型的接口程序,并采用切线刚度算法，通过与ABAQUS自带本构关系计算的结果相比较，验证其正确性。(This paper studies the user subroutine UMAT of ABAQUS development methods, the use of FORTRAN language isotropic hardening material model of the interface program, studied the effects of such material is extremely elastic-plastic constitutive relation method. This article UMAT tightly around the secondary development of technology, the first principle of its interface detail, and then for the theory of nonlinear finite element incremental stiffness of the regular tangent stiffness method and the theory of algorithms to do an in-depth analysis of deduced a regular tangent stiffness and rigidity of the law of the specific expression of algorithm theory, and then the preparation of the two algorithms, respectively, of the UMAT program, and finally the establishment of a specific model checking, bringing with ABAQUS elasto-plastic constitutive relation of the calculated results compared to verify the correctness of the two.)

根据物理学的毕奥-萨法尔定理，计算环形线圈周围电磁场的强度。。(According to physics, Biot- Safar theorem, calculate the intensity of electromagnetic field around the circular coil. .)

说明：  用C语言实现计算两个数字的最大公约数，代码简单简洁，适合初学者学习。(C language is used to calculate the maximum common divisor of two digits. The code is simple and concise. It is suitable for beginners to learn.)

FLUENT里面改进的SA湍流模型，为UDF文件，可以进行链接编译计算(FLUENT which improved SA turbulence model for the UDF file can be compiled to calculate the link)

格子玻尔兹曼 圆柱绕流 Python编写(lattice boltzmann flow around a cylinder, using Python. very fast because of numpy library)