def test_whfast_democraticheliocentric(self):
current_function_name = inspect.stack()[0][3][5:] # Remove first 5 characters "test_"
expected_json_filename, json_filename = common.setup(self.current_dirname, self.current_filename, current_function_name)
initial_time, time_step, time_limit, historic_snapshot_period, recovery_snapshot_period = common.simulation_properties()
consider_effects = posidonius.ConsiderEffects({
"tides": True,
"rotational_flattening": True,
"general_relativity": True,
"disk": True,
"wind": True,
"evolution": True,
})
general_relativity_implementation = "Kidder1995" # Assumes one central massive body
#general_relativity_implementation = "Anderson1975" # Assumes one central massive body
#general_relativity_implementation = "Newhall1983" # Considers all bodies
universe = posidonius.Universe(initial_time, time_limit, time_step, recovery_snapshot_period, historic_snapshot_period, consider_effects)
star_mass = 0.08 # Solar masses
star_dissipation_factor_scale = 1.0
star_position = posidonius.Axes(0., 0., 0.)
star_velocity = posidonius.Axes(0., 0., 0.)
#star_evolution = posidonius.Baraffe1998(star_mass) # M-Dwarf (mass = 0.10) or SolarLike ConstantDissipation (mass = 1.0)
#star_evolution = posidonius.Baraffe2015(star_mass) # mass = 0.01 .. 1.40
star_evolution = posidonius.Leconte2011(star_mass) # BrownDwarf (mass = 0.01 .. 0.08)
#star_evolution = posidonius.BolmontMathis2016(star_mass) # SolarLike Evolving dissipation (mass = 0.40 .. 1.40)
#star_evolution = posidonius.GalletBolmont2017(star_mass) # SolarLike Evolving dissipation (mass = 0.30 .. 1.40)
#star_evolution = posidonius.LeconteChabrier2013(False) # Jupiter without dissipation of dynamical tides
#star_evolution = posidonius.LeconteChabrier2013(True) # Jupiter with dissipation of dynamical tides
#star_evolution = posidonius.NonEvolving()
star = common.brown_dwarf(star_mass, star_dissipation_factor_scale, star_position, star_velocity, general_relativity_implementation, star_evolution)
universe.add_particle(star)
common.basic_configuration(universe)
############################################################################
#whfast_alternative_coordinates="Jacobi"
whfast_alternative_coordinates="DemocraticHeliocentric"
#whfast_alternative_coordinates="WHDS"
#universe.write(json_filename, integrator="LeapFrog")
#universe.write(json_filename, integrator="IAS15")
universe.write(json_filename, integrator="WHFast", whfast_alternative_coordinates=whfast_alternative_coordinates)
if not os.path.exists(expected_json_filename):
shutil.copyfile(json_filename, expected_json_filename)
self.assertTrue(filecmp.cmp(json_filename, expected_json_filename, shallow=False), "Generated JSON case is not equal to the expected one: {} {}".format(json_filename, expected_json_filename))
shutil.rmtree(os.path.dirname(json_filename))
initial_time = 1.0e6 * 365.25 # time [days] where simulation starts
time_step = 0.005 # days
#time_limit = 4*time_step # days
time_limit = 365.25 * 1.0e8 # days
historic_snapshot_period = 100. * 365.25 # days
recovery_snapshot_period = 100. * historic_snapshot_period # days
consider_effects = posidonius.ConsiderEffects({
"tides": True,
"rotational_flattening": False,
"general_relativity": False,
"disk": False,
"wind": False,
"evolution": False,
})
universe = posidonius.Universe(initial_time, time_limit, time_step,
recovery_snapshot_period,
historic_snapshot_period, consider_effects)
star_mass = 0.08 # Solar masses
star_radius_factor = 0.845649342247916
# [start correction] -------------------------------------------------------
# To reproduce Bolmont et al. 2015:
# Mercury-T was using R_SUN of 4.67920694e-3 AU which is not the IAU accepted value
# thus, to reproduce Mercury-T results the star radius factor should be slighly modified:
star_radius_factor = star_radius_factor * (4.67920694e-3 /
posidonius.constants.R_SUN)
# [end correction] ---------------------------------------------------------
star_radius = star_radius_factor * posidonius.constants.R_SUN
star_radius_of_gyration = 4.41e-01 # Brown dwarf
star_position = posidonius.Axes(0., 0., 0.)