2维euler流场求解器

******************************************************************************** U N S T R U C T 2 D (c) 1997-2014 Jiri Blazek, CFD Consulting & Analysis, www.cfd-ca.de ******************************************************************************** Program for the solution of 2-D Euler and Navier-Stokes equations on unstructured triangular grids. Median-dual finite-volume scheme is employed for the spatial discretisation together with Roe's upwind scheme. The equations are integrated in time using an explicit multistage time-stepping scheme. The program also offers the possibility to simulate incompressible flows at very low Mach numbers. Further details are provided in Subsection 12.7 of the book. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. -------------------------------------------------------------------------------- Files -------------------------------------------------------------------------------- doc - HTML documentation (files, modules, functions and variables; point your browser to doc/html/index.html) run - test cases (grids and topology files, user input files, results) src - source code The following test cases are provided in the directory "run": channel - inviscid, transonic flow in a channel with 10% circular bump fplate - laminar viscous flow past a flat plate n0012 - inviscid, transonic flow around NACA 0012 airfoil n4415_20 - inviscid, incompressible flow around NACA 4415 airfoil with flap vki1 - inviscid, transonic flow inside VKI-1 turbine cascade (Kiock, R.; Lehthaus, F.; Baines, N.C.; Sieverding, C.H.: "The Transonic Flow Through a Plane Turbine Cascade as Measured in Four European Wind Tunnels". ASME J. Engineering Gas Turbines and Power, 108 (1986), pp. 277-284) Files with the extension "ugr" contain the grid. Files with "_input" added to the case name represent user input files. Furthermore, "iso" in the name signifies a plot file containing the complete 2-D flow-field, whereas "surf" stands for the surface only. The directory "run" contains in "Unstruct2D.exe" the executable program for 64-bit Windows platforms (Win 7 and higher). -------------------------------------------------------------------------------- How to compile "Unstruct2D" -------------------------------------------------------------------------------- For the compilation of the sources in "src", any decent Fortran-90 compiler is sufficient. If you have none installed, GNU's freely available gfortran compiler is highly recommendable for the purpose. On Windows, the compiler is provided in the MinGW package. An easy to install distribution can be downloaded at: www.tdm-gcc.tdragon.net/download. It offers the possibility to compile the sources to either 32- or 64-bit executable. The directory "src" contains also project file for the Code::Blocks (www.codeblocks.org) integrated development environment, which has a very nice plug-in for Fortran-90 projects. The IDE is available for free for all major platforms. But of course, you can use your favorite IDE or just an editor as well. For this purpose, a Makefile is provided in "src". The file "main.f90" contains the main program, module files are named "mod*.f90". -------------------------------------------------------------------------------- How to run "Unstruct2D" -------------------------------------------------------------------------------- The program requires a number of user input parameters which determine the fluid properties, set the boundary conditions, control the program execution, and the output of the results. The user parameters are stored in a plain ASCII file. Examples are provided in the files "*_input_*" in the directory "run". In order to run "Unstruct2D", open a terminal window (Command Prompt on Windows), change to the directory where the grid and user input files are located and type at the prompt: > Unstruct2D input_file where "input_file" is the path and name of the file with user parameters (e.g., "channel_input"). Depending on how your environment is set up (PATH variable), you might have to specify the full path to the executable as well. During and after the run, the program generates four output files: convergence history, data for isoplots, distribution of flow quantities along wall(s) and a restart file. The data in the convergence and in the both plot files are stored in Vis2D format and can be visualized using the commercial plotting software available from CFD Consulting & Analysis (www.cfd-ca.de). In the case of external flows, file with the convergence history contains the following quantities: step - iteration number resid - density based convergence measure (see Eq. (12.1)) resmax - maximum difference between new and old density [kg/m^3] i-res - index of the grid node where resmax is found cl - lift coefficient } cd - drag coefficient } considering pressure forces only! cm - moment coefficient } Lift, drag and moment coefficients are replaced by: mass-flow - average mass flow rate [kg/s] mass-ratio - ratio of mass flow at outlet to mass flow at inlet for internal flows. The file for the generation of isoplots always contains the grid coordinates (denoted as x, y). Additionally, the following quantities are written out for each grid point, if switched on in the user input file (last section): density - density [kg/m^3] u - x-component of the velocity [m/s] v - y-component of the velocity [m/s] p - static pressure [Pa] p-tot - total pressure [Pa] T - static temperature [K] T-tot - total temperature [K] M - local Mach number M-isen - isentropic Mach number pt-loss - total pressure loss visc-lam - laminar viscosity coefficient (dynamic) [kg/ms] cf - skin friction coefficient (boundaries only) -Cp - pressure coefficient (boundaries only) Variables in the convergence and in the plot files are stored column-wise. Please note that all physical quantities are defined in SI units. In order to run "Unstruct2D", a grid file must be provided. The grid file contains the dimensions of the grid, the description of the boundary faces, the Cartesian coordinates of the nodes and the nodes of the triangles. The format of the grid file is as follows: (1) dimensions (one line): - number of grid nodes (NO dummy nodes) - number of triangular cells, - number of boundary conditions (2) for each boundary condition (two lines): - type 100-199 = inflow 200-299 = outflow 300-399 = viscous wall 400-499 = inviscid wall 500-599 = symmetry line 600-699 = farfield 700-799 = periodic boundary - index of the last boundary face (NOT used for periodic boundaries) - index of the last boundary point - name (on new line) (3) list of boundary faces (2 nodes of a face, arbitrary oriented) for all boundary conditions except if the corresponding boundary is periodic, then the list contains the two related periodic nodes instead (4) Cartesian coordinates of the nodes (first column is x, second is y) (5) indices of three nodes defining a triangle; the orientation is arbitrar