Wave-propagation

Below is just a small exerpt of the full statement Statement.pdf.

Wave propagation at the surface of the ocean can be modelled using the so-called “shallow water” equations, which are derived by depth-integrating the Navier-Stokes equations. The domain of study is a rectangle [0, a] × [0, b] whose dimensions and bathymetric map (map of h(x, y)) are given by an input file. Sample input files are provided in the directory [Maps/]

In the Scripts directory are multiple bash scripts and Slurm scripts to run the program on a cluster. There are 2 python scripts, contour_plot.py to display the input map files and the output files eta_XXX.dat, u_XXX.dat and v_XXX.dat and plot.py to plot the scalabilty of the program using data gathered from running the program using the parameter files in Report/Parameters.

A full analysis can be seen in the Report Report.pdf.

Getting Started

This can be run on a local machine or on a cluster using a Slurm script.

Prerequisites

Make sure that you have gcc installed using the command below:

sudo apt-get install gcc

OpenMP comes with the gcc compiler.

Next, you'll have to install OpenMPI to do multiprocess computation. There are may possible ways, one of which is to build it from source here.

This project was compiled and run using gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0 and opemmpi mpirun (Open MPI) 2.1.1 . If you want to make sure it works, I invite you to install the same one. You can check your version with

gcc --version

and

mpirun --version

Compilation

Locally

To compile the program and run it locally (on your machine), run the following commands in the terminal.

mpicc project2_Delaunoy_Crasset*.c -std=c99 -lm -fopenmp -o waves               

and run the program using the template

OMP_NUM_THREADS=NB_OF_THREADS mpirun -np NB_PROCESSORS waves PARAMETER_FILE  MAP_FILE FINITE_DIFFERENCE_SCHEME

Replace NB_OF_THREADS with the number of threads you wish to run it with, NB_PROCESSORS with the number of processes you want to launch, PARAMETER_FILE with one of the parameters files in direcotry Parameters/ or Report/Parameters and MAP_FILE with a bathymetric map file in directory Maps/. Lastly, choose the FINITE_DIFFERENCE_SCHEME that you want, 0 for the explicit scheme and 1 for the implicit scheme.

For example,

Running the implicit scheme on the map sriLanka using 2 threads and 1 process.

OMP_NUM_THREADS=2 mpirun -np 1 waves Parameters/sriLanka_implicit_result.txt  Maps/sriLanka.dat 1

Running the explicit scheme on the map sriLanka using 4 threads and 2 process.

OMP_NUM_THREADS=4 mpirun -np 2 waves Parameters/sriLanka_explicit_result.txt  Maps/sriLanka.dat 0

On a cluster with Slurm

If you want to fully use the capabilities of the program, we suggest you run this code on a cluster managed by the Slurm Workload Manager.

Sample scripts are provided in the Scripts/ directory.

Authors

• **Arnaud Delaunoy ** - Implementation of the problem, scalability and stability analysis

• **Tom Crasset ** - Implementation of the problem, scalability and stability analysis

• **Anthony Royer ** - Creation of statement, provided map files and makeMovie.m to create a video of the wave propagation.

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments

Thanks to Pr. C. Geuzaine for his course of High Perfomance Scientific Computing at the University of Liège as well as his assistant, Anthony Royer. Moreover, we would like to thank the CECI(Consortium des Équipements de Calcul Intensif) for the cluster they provided.