Command line

Basics

nsfds3 can be used from a terminal with:

nsfds3 solve|make|show

solve : solves Navier-Stokes equation using a default configuration
make : makes movie or sound files from results obtained with solve subcommand
show : set of commands to display simulations parameters, grid or to inspect simulation results

See -h option for further help:

nsfds3 solve -h
nsfds3 make -h               # 'movie' and 'sound' subcommands
nsfds3 show -h               # 'parameters', 'grid', 'frame', 'probes', 'spectrogram' subcommands

The solve subcommand

The solve subcommand launch the solver. By default, the solver uses the last configuration used (or the default configuration from nsfds3.solver.CfgSetup() if it does not found any last configuration). To target a configuration file, use the -c argument as follows:

nsfds3 solve -c my_config_file.conf

To see other options:

nsfds3 solver -h

The make subcommand

The make subcommand can either generate movie (.mp4 file) or sound (.wav file) from an hdf5 file:

nsfds3 make sound
nsfds3 make movie

Work with sounds

Sounds are generated from the probes (pressure) saved in the data file (hdf5 file). If no probe has been set in the computation domain, no sound will be generated from nsfds3 make sound.

Work with movies

Movies can be created from an hdf5 file (or using the .cfg file of the simulation) if the save option has been selected. Then, the following variables are allowed as argument of the movie subcommand:

var	variable
p	pressure
rho	density
vx	x component of the velocity
vy	y component of the velocity
vz	z component of the velocity (only for 3d)
e	energy
wz	z component of the vorticity
wy	y component of the vorticity (only for 3d)
wx	x component of the vorticity (only for 3d)

For instance, to create a movie of the x-component of the velocity, one can use:

nsfds3 make movie vx -c my_confif_file.conf

or directly from a target data file:

nsfds3 make movie rho -d my_data_file.hdf5

The show subcommand

The show subcommand provides a set of commands to show simulation parameters, results, or grid configuration. The main show subcommands are:

frame:: Display an acoustic variable at a given iteration (works like movie)
probes:: Display pressure field(s) as a function of time at probe location(s)
spectrogram:: Display spectrogram(s) at probe location(s)
parameters:: Display some simulation parameters
grid:: Display the grid
domains:: Display the computation domains (only is free=False)

For instance, to display the density at iteration 100:

nsfds3 show frame rho -n 100 -d my_data_file.hdf5