Least-Squre

自己写了一个二维Euler方程的间断有限元程序 上次发了一个三角形单元的程序 因为不是曲边单元 所以在圆柱后面容易形成涡 现在把程序改为曲边四边形单元了 没有涡出现 单元是8节点四边形单元 节点编号顺序是 1 5 2 6 3 7 4 8 也就是四个角点依次 是1 2 3 4 然后是边的中点编号 5 6 7 8. 时间推进采用 Runge-Kutta 方法 数值通量采用全局Lax-Friedrichs通量 仍然不能捕捉激波 因为没有做重构或者加人工粘性 等这个做出来了 再发一次。 程序没有进行优化 比如说内存的消耗没有优化 比如直边单元的边界积分仍然采 用了曲边的积分方法 增加了计算量 比如面积分、线积分都是采用的是Gauss- Legendre-Lobatto积分 积分精度会比一般的Gauss-Legendre积分精度低一阶 等 等问题。 二维的 纯属交流性质 就没有考虑这些问题 ^_^ 如果物面全部是直边 那么只要改变一个参数N 就可以获得不同的计算精度 且具 有谱精度 因为单元的节点是Gauss-Legendre-Lobatto积分点。 其实就是谱元法 （物面是曲边的情况我不清楚是不是也可以通过提高基函数的阶数 也就是增加N 来提高计算精度）(Wrote a two-dimensional Euler equations with discontinuous finite element program Last made ​ ​ a triangular element of the program, not curved edge unit is so easy to form a vortex in the cylinder behind the Program to curved edge quadrilateral element vortices appear Unit is the order of 8-node quadrilateral element node number is 15,263,748 which is the four corners of the points in turn Is 1234 and then the side of the midpoint of the number 5678. Time promote the use of Runge-Kutta method Numerical flux of the overall situation of Lax-Friedrichs, flux Still can not capture the shock wave did not do the reconstruction or artificial viscosity do it Zaifayici. The program is not optimized for example, memory consumption is not optimized such as straight-edge boundary integral of the unit is still mining Integral method to increase the amount of computation such as surface integral with a curved edge, the line integral using the Gauss- The Legendr)

划分网格一个开源的库，有限元的算法，很好用(Meshing an open source library = for finite element)

说明：  在进行激光熔覆或者焊接时可用到的移动热源命令流(Command flow of moving heat source available during laser cladding or welding)

说明：  fluent中作液体蒸发相变的udf，非常专业，证明可行(fluent in the evaporation of liquid phase transition for udf, very professional, proved to be feasible)

实现构建矩阵，矩阵的相加，相减，清零，以及转置，还有相乘的功能。(To build matrix, the matrix addition, subtraction, reset, and transposed, and the function of the multiplication. )

工程领域，PR方程代码.用于计算混合工质性质。(PR equation code)

基于Visual C++的地震信号处理程序源代码，包括常用的FFT和Hilbert变换代码。(Visual C++ based on the seismic signal processing program source code, including the commonly used FFT and Hilbert transform code.)

说明：  矩形件排样的模拟退火算法求解 适用于矩形件的排样(Rectangular pieces of nesting of simulated annealing algorithm for nesting of rectangular parts)

求解四元三次方程组，通过在VC++的编程环境，实现计算的高速运行(Solving four yuan cubic equations by VC++ programming environment, to achieve high-speed operation calculated)

处理大规模矩阵，对大规模的矩阵进行分解，即形如分解A=UV(To deal with large-scale matrix, mass matrix decomposition, that is shaped like a decomposition A = UV)