NavierStokes:Navier Stokes方程的求解器

# nstokes [](https://travis-ci.org/ISCDtoolbox/NavierStokes) Nstokes is a finite element solver for Stokes and Navier-Stokes incompressible flow problems in two and three dimensions. #### Installation 1. you will need to install the [ISCD Commons Library](https://github.com/ISCDtoolbox/Commons) on your system. Please refer to the instructions provided on the ISCD Commons Library page in order to install this library. 2. download the zip archive of NavierStokes or clone this repository: ` git clone https://github.com/ISCDtoolbox/NavierStokes.git ` navigate to the downloaded directory: ` cd NavierStokes ` then create build directory and compile the project using cmake ``` mkdir build cd build cmake .. make make install ``` #### Usage After compiling nstokes as described above, you should have an executable file in your $HOME/bin directory. If your PATH variable is correctly set to this directory, nstokes can be called with the following syntax: usage: nstokes [+/-v | -h | -N] [-dt step] [-mt val] [-nt n] [-n nit] [-r res] [-t typ] [-ts n] source[.mesh] [-p param[.nstokes]] [-s data[.sol]] [-o output[.sol]] The square braces indicate optional arguments. Some commands have flags, some others do not. The options and flags are: ``` --help show the syntax and exit. --version show the version and date of release and exit. -N Navier-Stokes solver (default Stokes) -dt step time step (time units) -mt val max time (time units) -nt n number of time steps -n nit number of iterations max for convergence -r res value of the residual (Krylov space) for convergence -t typ specify the type of FE space: 1: P1bP1(*), 2: P2P1 -v suppress any message (for use with function call). +v increase the verbosity level for output. -w save vorticity file. source.mesh name of the mesh file param.nstokes name of file containing fluid parameters data.sol name of file containing the initial solution or boundary conditions output.sol name of the output file (velocity+pressure) ``` A full description of all parameters and options that can be specified in the command line or in a parameter file [file.nstokes] can be found in the project [wiki](https://github.com/ISCDtoolbox/NavierStokes/wiki). #### Quickstart You can test the installation and look at examples by entering the [demos](demos) directory and running the program: cd demos/2d nstokes cavity.mesh # or equivalently: nstokes cavity.mesh -p cavity.nstokes -o cavity.sol that will produce an output that will look like: ``` user:~/code/NavierStokes/demos/2d$ nstokes cavity.mesh - NSTOKES, Release 5.2a, Jan. 29, 2016 (C) Copyright 2006- , ICS-SU - LOADING DATA cavity.mesh: 555 vertices, 74 edges, 1034 triangles cavity.nstokes: 2 parameters - COMPLETED: 0.002s ** MODULE NSTOKES: 5.2a Matrix and right-hand side assembly Solving linear system: pressure: res=6.862905e-07, nit=36 velocity: res=7.920541e-07, nit=26 ** COMPLETED: 0.120s - WRITING DATA cavity.solb: 555 data vectors - COMPLETED: 0.008s ** Cumulative time: 0.130s. ``` #### Authors & contributors * nstokes has been initiated by Thi Thu Cuc Bui, Dena Kazerani, Thi Thanh Mai Ta and Pascal Frey (Université Pierre et Marie Curie). * Contributors to this project are warmly welcomed. #### License nstokes is given under the [terms of the GNU Lesser General Public License] (LICENSE.md).