Shows the propagation of a sound wave through the grid. The test consists of a linear wave of amplitude 1e-4 on a background density of 1.0 and pressure of 0.6. Gamma is set to 1.666666666666667. This test is performed with the default hydro build (cholla/builds/make.type.hydro). Full initial conditions can be found in cholla/src/grid/initial_conditions.cppunder Sound_Wave()
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# Parameter File for sound wave test
#
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# number of grid cells in the x dimension
nx=256
# number of grid cells in the y dimension
ny=256
# number of grid cells in the z dimension
nz=256
# final output time
tout=0.05
# time interval for output
outstep=0.01
# name of initial conditions
init=Sound_Wave
# domain properties
xmin=0.0
ymin=0.0
zmin=0.0
xlen=4.0
ylen=4.0
zlen=4.0
# type of boundary conditions
xl_bcnd=1
xu_bcnd=1
yl_bcnd=1
yu_bcnd=1
zl_bcnd=1
zu_bcnd=1
# path to output directory
outdir=./
#################################################
# Parameters for linear wave problems
# initial density
rho=1.0
# velocity in the x direction
vx=0
# velocity in the y direction
vy=0
# velocity in the z direction
vz=0
# initial pressure
P=0.6
# amplitude of perturbing oscillations
A=1e-4
# value of gamma
gamma=1.666666666666667
Upon completion, you should obtain five output files. The wave is easier to see by increasing tout. Here, we see the evolution of the density and pressure at 10 fps: