Shallow_water_FV

A Fortran program that solves the 2D shallow water equations with a finite volume method based on a van Leer Q-scheme.

This program solves the two-dimensional shallow water equations with both the bed slope and bed+wall friction. The numerical discretization is based on a finite volume method with a upwind van Leer Q-scheme used for the flux terms and for the geometrical source term. A third order Total Variation Diminishing Runge-Kutta and a fourth order explicit Runge-Kutta time integration methods are implemented. Steady and unsteady computations can be simulated by switching on/off a local time stepping calculation. Further information can be found in the documentation shallow_water.pdf.

Organization

• Doc: this folder contains the PDF file that explains the theory and shows the results from the program on several test cases.
• Examples: this folder contains some test cases that are helpful to get used to the program. A PDF file explains the tests cases and the operations to be done to perform computations.
• SRC: this folder contains the source code

Get the code

You can get the latest code by cloning the master branch:

git clone https://github.com/xavierdechamps/Shallow_water_FV.git

or by downloading it as a zip file.

Build the code

The code can be compiled by CMake as the necessary files (CMakeLists.txt and CMake.config) are provided. The user can modify the content of CMake.config to his/her own configuration, in particular the parameters Windows, Have_SigWatch, Have_Gnuplot and Have_OpenMP. The parameter MANGLING is required to link with the external library sigwatch. Depending on you compiler you may choose between uppercase/lowercase with addition of a trailer "_" or not. On Linux you can get the name mangling with the command "nm libsigwatch.a". On Windows you get the name mangling with the command "dumpbin /ALL sigwatch.lib". The parallelism inside the subroutine flux.f90 with OpenMP can be tuned by setting the number of threads to use (environment variable OMP_NUM_THREADS).

mkdir build
cd build
cmake ..
make

Hereunder an example of a supercritical flow inside a converging channel: