def slowtest1(self):
stellar_evolution = self.new_instance(MESA)
stellar_evolution.particles.add_particles(Particles(2, mass=[1.0, 5.0]|units.MSun))
stellar_evolution.evolve_model(10.0 | units.Myr)
initial_separation = stellar_evolution.particles.radius.sum()
sph_particles_1 = convert_stellar_model_to_SPH(
stellar_evolution.particles[0],
200,
seed=12345
).gas_particles
sph_particles_2 = convert_stellar_model_to_SPH(
stellar_evolution.particles[1],
1000,
seed=12345
).gas_particles
stellar_evolution.stop()
initial_speed = 10.0 | units.km / units.s
sph_particles_2.x += initial_separation
sph_particles_1.vx += initial_speed
all_sph_particles = ParticlesSuperset([sph_particles_1, sph_particles_2])
all_sph_particles.move_to_center()
t_end = 4.0e3 | units.s
print "Evolving to:", t_end
n_steps = 4
unit_system_converter = ConvertBetweenGenericAndSiUnits(1.0 | units.RSun, 1.0 | units.MSun, t_end)
hydro_code = Gadget2(unit_system_converter)
hydro_code.gas_particles.add_particles(all_sph_particles)
pyplot.ion()
for time in [i*t_end/n_steps for i in range(1, n_steps+1)]:
hydro_code.evolve_model(time)
pyplot.close('all')
pyplot.figure()
pynbody_column_density_plot(hydro_code.gas_particles, width=10|units.RSun)
pyplot.draw()
pyplot.figure()
loglog(hydro_code.gas_particles.position.lengths_squared(), hydro_code.gas_particles.pressure, 'bo')
pyplot.draw()
hydro_code.stop()
sleep(3)
pyplot.ioff()
def convert_star_to_hydro_model(M, t_end):
stellar_evolution = EVtwin()
star = stellar_evolution.particles.add_particle(Particle(mass=M))
stellar_evolution.evolve_model(t_end)
Ngas = 10000
sph_particles = convert_stellar_model_to_SPH(star, Ngas).gas_particles
stellar_evolution.stop()
return sph_particles
def slowtest1(self):
stellar_evolution = self.new_instance(MESA)
stellar_evolution.particles.add_particles(
Particles(2, mass=[1.0, 5.0] | units.MSun))
stellar_evolution.evolve_model(10.0 | units.Myr)
initial_separation = stellar_evolution.particles.radius.sum()
sph_particles_1 = convert_stellar_model_to_SPH(
stellar_evolution.particles[0], 200, seed=12345).gas_particles
sph_particles_2 = convert_stellar_model_to_SPH(
stellar_evolution.particles[1], 1000, seed=12345).gas_particles
stellar_evolution.stop()
initial_speed = 10.0 | units.km / units.s
sph_particles_2.x += initial_separation
sph_particles_1.vx += initial_speed
all_sph_particles = ParticlesSuperset(
[sph_particles_1, sph_particles_2])
all_sph_particles.move_to_center()
t_end = 4.0e3 | units.s
print "Evolving to:", t_end
n_steps = 4
unit_system_converter = ConvertBetweenGenericAndSiUnits(
1.0 | units.RSun, 1.0 | units.MSun, t_end)
hydro_code = Gadget2(unit_system_converter)
hydro_code.gas_particles.add_particles(all_sph_particles)
pyplot.ion()
for time in [i * t_end / n_steps for i in range(1, n_steps + 1)]:
hydro_code.evolve_model(time)
pyplot.close('all')
pyplot.figure()
pynbody_column_density_plot(hydro_code.gas_particles,
width=10 | units.RSun)
pyplot.draw()
pyplot.figure()
loglog(hydro_code.gas_particles.position.lengths_squared(),
hydro_code.gas_particles.pressure, 'bo')
pyplot.draw()
hydro_code.stop()
sleep(3)
pyplot.ioff()
def convert_giant_to_sph(view_on_se_giant, number_of_sph_particles):
giant_in_sph = convert_stellar_model_to_SPH(
view_on_se_giant,
number_of_sph_particles,
with_core_particle = True,
target_core_mass = 1.4 | units.MSun,
do_store_composition = False
)
return giant_in_sph
def convert_giant_to_sph(view_on_se_giant, number_of_sph_particles):
giant_in_sph = convert_stellar_model_to_SPH(
view_on_se_giant,
number_of_sph_particles,
with_core_particle = True,
target_core_mass = 1.4 | units.MSun,
do_store_composition = False
)
return giant_in_sph
def convert_stars(self, particles, stellar_evolution_code):
n_particles = self.divide_number_of_particles(particles)
se_colliders = particles.get_intersecting_subset_in(stellar_evolution_code.particles)
if self.verbose:
print("Converting stars of {0} to SPH models of {1} particles, respectively.".format(particles.mass, n_particles))
sph_models = (
self.relax(convert_stellar_model_to_SPH(se_colliders[0], n_particles[0], **self.star_to_sph_arguments)),
self.relax(convert_stellar_model_to_SPH(se_colliders[1], n_particles[1], **self.star_to_sph_arguments))
)
gas_particles = Particles()
for particle, sph_model in zip(particles, sph_models):
sph_model.position += particle.position
sph_model.velocity += particle.velocity
gas_particles.add_particles(sph_model)
if self.verbose:
print("Converting stars to SPH particles done")
if self.debug:
print(gas_particles)
return gas_particles
def convert_stars(self, particles, stellar_evolution_code):
n_particles = self.divide_number_of_particles(particles)
se_colliders = particles.get_intersecting_subset_in(stellar_evolution_code.particles)
if self.verbose:
print "Converting stars of {0} to SPH models of {1} particles, respectively.".format(particles.mass, n_particles)
sph_models = (
self.relax(convert_stellar_model_to_SPH(se_colliders[0], n_particles[0], **self.star_to_sph_arguments)),
self.relax(convert_stellar_model_to_SPH(se_colliders[1], n_particles[1], **self.star_to_sph_arguments))
)
gas_particles = Particles()
for particle, sph_model in zip(particles, sph_models):
sph_model.position += particle.position
sph_model.velocity += particle.velocity
gas_particles.add_particles(sph_model)
if self.verbose:
print "Converting stars to SPH particles done"
if self.debug:
print gas_particles
return gas_particles
def star_to_sph(star, number_of_sph_particles):
stellar_evolution = stellar_evolution_code()
se_star = stellar_evolution.particles.add_particle(star)
stellar_evolution.evolve_model(22.7 | units.Myr)
model = convert_stellar_model_to_SPH(se_star,
number_of_sph_particles,
do_store_composition=False,
base_grid_options=dict(type="fcc"))
stellar_evolution.stop()
sph_star = model.gas_particles
sph_star.position += star.position
sph_star.velocity += star.velocity
return sph_star
def create_particles():
star = Particle()
star.mass = 3.0 | units.MSun
stellar_evolution = EVtwin()
se_star = stellar_evolution.particles.add_particle(star)
print("Evolving", star.mass, "star with",
stellar_evolution.__class__.__name__, "up to", 100 | units.Myr)
stellar_evolution.evolve_model(100 | units.Myr)
print("Creating SPH particles from the (1D) stellar evolution model")
sph_particles = convert_stellar_model_to_SPH(se_star, 1000).gas_particles
stellar_evolution.stop()
return sph_particles
def set_up_sph_giant(giant, stellar_structure_file, number_of_sph_particles):
model = convert_stellar_model_to_SPH(None,
number_of_sph_particles,
pickle_file=stellar_structure_file,
with_core_particle=True,
target_core_mass=2.0 | units.MSun,
do_store_composition=False,
base_grid_options=dict(type="fcc"))
sph_giant = model.gas_particles
core = model.core_particle
sph_giant.position += giant.position
sph_giant.velocity += giant.velocity
core.position += giant.position
core.velocity += giant.velocity
print "Core radius:", model.core_radius.as_string_in(units.RSun)
return sph_giant, core, model.core_radius
def create_particles():
star = Particle()
star.mass = 3.0 | units.MSun
stellar_evolution = EVtwin()
se_star = stellar_evolution.particles.add_particle(star)
print("Evolving", star.mass, "star with", stellar_evolution.__class__.__name__, "up to", 100 | units.Myr)
stellar_evolution.evolve_model(100 | units.Myr)
print("Creating SPH particles from the (1D) stellar evolution model")
sph_particles = convert_stellar_model_to_SPH(
se_star,
1000
).gas_particles
stellar_evolution.stop()
return sph_particles
def star_to_sph(mass, age, omega, Nsph):
stellar = evolve_star(mass, age)
new_age = stellar.model_time
star = stellar.particles[0]
if star.core_mass>zero:
with_core_particle = True
target_core_mass = coremass
else:
with_core_particle = False
target_core_mass = 0|units.MSun
m_sph = (star.mass-target_core_mass)/float(Nsph)
print "N_sph=", Nsph, m_sph.in_(units.MSun)
print "Target core mass:", target_core_mass
model = convert_stellar_model_to_SPH(
star,
Nsph,
with_core_particle = with_core_particle,
target_core_mass = target_core_mass,
do_store_composition = False,
base_grid_options=dict(type="fcc")
)
print "Final star:", star
age = stellar.model_time
M_scale = star.mass
R_scale = star.radius
stellar.stop()
core = model.core_particle
print "core", core
if core is None:
print "Make zero mass core"
core = Particle(mass=0|units.MSun, radius=1|units.RSun)
core.position = (0,0,0) | units.AU
core.velocity = (0,0,0) | units.kms
sph_star = model.gas_particles
print "Add Spin to star:", omega
sph_star.add_spin(omega)
relaxed_sph_star, core_particles = relax_sph_realization(sph_star, core)
return relaxed_sph_star, core_particles, age
def star_to_sph(stellar, omega, Nsph):
new_age = stellar.model_time
star = stellar.particles[0]
if star.core_mass>zero:
with_core_particle = True
target_core_mass = coremass
else:
with_core_particle = False
target_core_mass = 0|units.MSun
m_sph = (star.mass-target_core_mass)/float(Nsph)
print "N_sph=", Nsph, m_sph.in_(units.MSun)
print "Target core mass:", target_core_mass
model = convert_stellar_model_to_SPH(
star,
Nsph,
with_core_particle = with_core_particle,
target_core_mass = target_core_mass,
do_store_composition = False,
base_grid_options=dict(type="fcc")
)
print "Final star:", star
age = stellar.model_time
M_scale = star.mass
R_scale = star.radius
stellar.stop()
core = model.core_particle
print "core", core
if core is None:
print "Make zero mass core"
core = Particle(mass=0|units.MSun, radius=1|units.RSun)
core.position = (0,0,0) | units.AU
core.velocity = (0,0,0) | units.kms
sph_star = model.gas_particles
print "Add Spin to star:", omega
sph_star.add_spin(omega)
relaxed_sph_star, core_particles = relax_sph_realization(sph_star, core)
return relaxed_sph_star, core_particles, age
def new_particles(self):
input_file = os.path.join(get_path_to_results(), "test_sph_to_star_input.hdf5")
if os.path.exists(input_file):
return read_set_from_file(input_file, "hdf5")
stellar_evolution = EVtwin()
stellar_evolution.particles.add_particle(Particle(mass=1.0|units.MSun))
stellar_evolution.evolve_model(100.0|units.Myr)
particles = convert_stellar_model_to_SPH(
stellar_evolution.particles[0],
500,
seed=12345
).gas_particles
stellar_evolution.stop()
hydrodynamics = Gadget2(ConvertBetweenGenericAndSiUnits(1.0|units.MSun, 1.0|units.RSun, 1.0e3|units.s))
hydrodynamics.gas_particles.add_particles(particles)
hydrodynamics.evolve_model(1.0|units.s)
hydrodynamics.gas_particles.copy_values_of_attributes_to(["density", "u", "pressure"], particles)
hydrodynamics.stop()
write_set_to_file(particles, input_file, "hdf5")
return particles
def new_particles(self):
input_file = os.path.join(get_path_to_results(),
"test_sph_to_star_input.hdf5")
if os.path.exists(input_file):
return read_set_from_file(input_file, "hdf5")
stellar_evolution = EVtwin()
stellar_evolution.particles.add_particle(
Particle(mass=1.0 | units.MSun))
stellar_evolution.evolve_model(100.0 | units.Myr)
particles = convert_stellar_model_to_SPH(
stellar_evolution.particles[0], 500, seed=12345).gas_particles
stellar_evolution.stop()
hydrodynamics = Gadget2(
ConvertBetweenGenericAndSiUnits(1.0 | units.MSun, 1.0 | units.RSun,
1.0e3 | units.s))
hydrodynamics.gas_particles.add_particles(particles)
hydrodynamics.evolve_model(1.0 | units.s)
hydrodynamics.gas_particles.copy_values_of_attributes_to(
["density", "u", "pressure"], particles)
hydrodynamics.stop()
write_set_to_file(particles, input_file, "hdf5")
return particles
def merge_two_stars_sph_and_evolve(Mprim, Msec, tcoll, tend):
stars = Particles(2)
stars[0].mass = Mprim
stars[1].mass = Msec
stellar = EVtwin()
stellar.particles.add_particle(stars[0])
stellar.particles.add_particle(stars[1])
time = [] | units.Myr
mass = [] | units.MSun
radius = [] | units.RSun
temperature = [] | units.K
luminosity = [] | units.LSun
while stellar.model_time < tcoll:
stellar.evolve_model()
time.append(stellar.model_time)
mass.append(stellar.particles[0].mass)
radius.append(stellar.particles[0].radius)
temperature.append(stellar.particles[0].temperature)
luminosity.append(stellar.particles[0].luminosity)
print "Time=", time[-1], mass[-1], radius[-1], \
temperature[-1].in_(units.K), luminosity[-1].in_(units.LSun)
n_normal = len(time)
print stars
Nprim = int(100*stellar.particles[0].mass.value_in(units.MSun))
mgas = stellar.particles[0].mass/Nprim
Nsec = int(stellar.particles[1].mass/mgas)
print "N gas=", Nprim, Nsec
sph_primary = convert_stellar_model_to_SPH(
stellar.particles[0],
Nprim,
seed=12345
).gas_particles
sph_secondary = convert_stellar_model_to_SPH(
stellar.particles[0],
Nsec,
seed=12345
).gas_particles
stellar.stop()
distance = 1 | units.RSun
sph_secondary.x += distance
sph_secondary.vx -= 1.7*numpy.sqrt(2*constants.G*stars.mass.sum()/distance)
sph_particles = Particles()
sph_particles.add_particles(sph_primary)
#sph_particles.add_particles(sph_secondary)
sph_particles.move_to_center()
converter = nbody_system.nbody_to_si(1|units.hour, 1|units.RSun)
hydrodynamics = Gadget2(converter)
hydrodynamics.gas_particles.add_particles(sph_particles)
hydrodynamics.evolve_model(10.0|units.hour)
hydrodynamics.gas_particles.copy_values_of_attributes_to(["density", "u",
"pressure"],
sph_particles)
hydrodynamics.stop()
print "N all=", len(sph_particles)
clumps = find_clumps(sph_particles, converter)
#sph_particles = clumps[0]
print "N blob=", len(sph_particles)
#plot_clumps(clumps)
#sph_merger = sph_particles[0]
print "convert SPH to stellar model"
merged_star = convert_SPH_to_stellar_model(sph_particles)
print "initiate stellar evolution model"
#stellar_evolution = MESA()
stellar_evolution = EVtwin(redirect="none")
stellar_evolution.new_particle_from_model(merged_star, 0.0|units.Myr)
print "star:", stellar_evolution.particles
print "evolve star"
#stellar_evolution.evolve_model(tend)
while stellar_evolution.model_time<(tend-tcoll):
stellar_evolution.evolve_model()
time.append(stellar_evolution.model_time)
mass.append(stellar_evolution.particles[0].mass)
radius.append(stellar_evolution.particles[0].radius)
temperature.append(stellar_evolution.particles[0].temperature)
luminosity.append(stellar_evolution.particles[0].luminosity)
print "Time=", time[-1], mass[-1], radius[-1], \
temperature[-1].in_(units.K), luminosity[-1].in_(units.LSun)
print stellar_evolution.particles
stellar_evolution.stop()
return time, mass, radius, temperature, luminosity, n_normal
def head_on_stellar_merger(
masses=[0.3, 3.0] | units.MSun,
star_age=310.0 | units.Myr,
maximally_evolved_stars=False,
initial_separation=4.0 | units.RSun,
angle=numpy.pi / 3,
initial_speed=3000.0 | units.km / units.s,
initial_speed_perpendicular=30.0 | units.km / units.s,
number_of_sph_particles=1000,
t_end=1.0e4 | units.s,
sph_code=Fi,
steps_per_snapshot=4,
snapshot_size=100,
use_stored_stellar_models=True
):
"""
masses: Mass of the two stars
star_age: Initial age of the stars (if maximally_evolved_stars is False)
maximally_evolved_stars: Evolve stars as far as the Stellar Evolution code
can get
number_of_sph_particles: Total number of particles of both stars, divided
according to their masses
t_end: (Physical, not computational) duration of the hydrodynamics
simulation
sph_code: Code to use for the hydrodynamics simulation
steps_per_snapshot: A hydroplot snapshot is generated each time after this
many steps (0 or None means no snapshots)
snapshot_size: Size of the snapshot in pixels along one dimension
use_stored_stellar_models: Flag to use previously stored stellar model
files (for speed-up).
"""
# Convert some of the input parameters to string, for use in output file
# names:
n_string = "n" + ("%1.0e" % (number_of_sph_particles)
).replace("+0", "").replace("+", "")
t_end_string = "t" + ("%1.0e" % (t_end.value_in(units.s))
).replace("+0", "").replace("+", "")
masses_string = (
"m1_"
+ (
"%0.3e" % (masses[0].value_in(units.MSun))
).replace("+0", "").replace("+", "")
+ "_m2_"
+ (
"%0.3e" % (masses[1].value_in(units.MSun))
).replace("+0", "").replace("+", "")
)
if maximally_evolved_stars:
star_age_string = "a_max"
else:
star_age_string = "a" + \
("%0.3e" % (star_age.value_in(units.Myr))).replace(
"+0", "").replace("+", "")
base_output_file_name = os.path.join(
get_path_to_results(), "stellar_merger_"+n_string+"_"+t_end_string)
pickle_file_1 = os.path.join(get_path_to_results(
), "stellar_merger_"+masses_string+"_"+star_age_string+"_1.pkl")
pickle_file_2 = os.path.join(get_path_to_results(
), "stellar_merger_"+masses_string+"_"+star_age_string+"_2.pkl")
if not use_stored_stellar_models or not (os.path.exists(pickle_file_1) and os.path.exists(pickle_file_2)):
stars = Particles(2)
stars.mass = masses
try:
stellar_evolution = MESA()
stellar_evolution.initialize_code()
except:
print("MESA was not built. Returning.")
return
stellar_evolution.commit_parameters()
stellar_evolution.particles.add_particles(stars)
stellar_evolution.commit_particles()
if maximally_evolved_stars:
try:
while True:
stellar_evolution.evolve_model()
except AmuseException as exception:
print(exception)
else:
stellar_evolution.evolve_model(star_age)
if os.path.exists(pickle_file_1):
print("Could not save stellar model 1: file already exists.")
else:
pickle_stellar_model(stellar_evolution.particles[0], pickle_file_1)
print("Stellar model 1 saved at:", pickle_file_1)
if os.path.exists(pickle_file_2):
print("Could not save stellar model 2: file already exists.")
else:
pickle_stellar_model(stellar_evolution.particles[1], pickle_file_2)
print("Stellar model 2 saved at:", pickle_file_2)
stellar_evolution.stop()
model_1 = StellarModel2SPH(None, None, pickle_file=pickle_file_1)
model_2 = StellarModel2SPH(None, None, pickle_file=pickle_file_2)
model_1.unpickle_stellar_structure()
model_2.unpickle_stellar_structure()
composition = model_2.composition_profile
midpoints = model_2.midpoints_profile[1:-1]
specific_internal_energy = model_2.specific_internal_energy_profile
number_of_sph_particles_1 = int(
round(
number_of_sph_particles
* (model_1.mass / (model_1.mass + model_2.mass))
)
)
number_of_sph_particles_2 = (
number_of_sph_particles
- number_of_sph_particles_1
)
print("Creating initial conditions from a MESA stellar evolution model:")
print(
model_1.mass,
"star consisting of",
number_of_sph_particles_1,
"particles."
)
sph_particles_1 = convert_stellar_model_to_SPH(
None,
number_of_sph_particles_1,
seed=12345,
pickle_file = pickle_file_1
).gas_particles
print(
model_2.mass,
"star consisting of",
number_of_sph_particles_2,
"particles."
)
sph_particles_2 = convert_stellar_model_to_SPH(
None,
number_of_sph_particles_2,
pickle_file=pickle_file_2
).gas_particles
initial_separation += model_1.radius + model_2.radius
sph_particles_2.x += numpy.cos(angle) * initial_separation
sph_particles_2.y += numpy.sin(angle) * initial_separation
sph_particles_1.vx += (
numpy.cos(angle) * initial_speed
- numpy.sin(angle) * initial_speed_perpendicular
)
sph_particles_1.vy += (
numpy.cos(angle) * initial_speed_perpendicular
+ numpy.sin(angle) * initial_speed
)
view = (
[-0.5, 0.5, -0.5, 0.5]
* (initial_separation + model_1.radius + model_2.radius)
)
all_sph_particles = ParticlesSuperset([sph_particles_1, sph_particles_2])
all_sph_particles.move_to_center()
unit_converter = ConvertBetweenGenericAndSiUnits(
1.0 | units.RSun, constants.G, t_end)
hydro_legacy_code = sph_code(unit_converter)
n_steps = 100
hydro_legacy_code.parameters.n_smooth = 96
try:
hydro_legacy_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if "parameter is read-only" not in str(exc):
raise
hydro_legacy_code.gas_particles.add_particles(all_sph_particles)
times = [] | units.Myr
kinetic_energies = [] | units.J
potential_energies = [] | units.J
thermal_energies = [] | units.J
print("Evolving to:", t_end)
for time, i_step in [(i*t_end/n_steps, i) for i in range(1, n_steps+1)]:
hydro_legacy_code.evolve_model(time)
times.append(time)
kinetic_energies.append(hydro_legacy_code.kinetic_energy)
potential_energies.append(hydro_legacy_code.potential_energy)
thermal_energies.append(hydro_legacy_code.thermal_energy)
if steps_per_snapshot and (not i_step % steps_per_snapshot):
hydro_plot(
view,
hydro_legacy_code,
(snapshot_size, snapshot_size),
base_output_file_name +
"_hydro_image{0:=03}.png".format(i_step)
)
hydro_legacy_code.gas_particles.new_channel_to(
all_sph_particles
).copy_attributes(
['mass', 'x', 'y', 'z', 'vx', 'vy', 'vz', 'u']
)
center_of_mass = all_sph_particles.center_of_mass(
).as_quantity_in(units.RSun)
center_of_mass_velocity = all_sph_particles.center_of_mass_velocity(
).as_quantity_in(units.km / units.s)
print()
print("center_of_mass:", center_of_mass)
print("center_of_mass_velocity:", center_of_mass_velocity)
all_sph_particles.position -= center_of_mass
sph_midpoints = all_sph_particles.position.lengths()
energy_plot(
times,
kinetic_energies, potential_energies, thermal_energies,
base_output_file_name+"_energy_evolution.png"
)
thermal_energy_plot(
times,
thermal_energies,
base_output_file_name+"_thermal_energy_evolution.png"
)
composition_comparison_plot(
midpoints, composition[0],
sph_midpoints, all_sph_particles.h1,
base_output_file_name+"_composition_h1.png"
)
internal_energy_comparison_plot(
midpoints, specific_internal_energy,
sph_midpoints, all_sph_particles.u,
base_output_file_name+"_new_u.png"
)
hydro_plot(
[-2.0, 2.0, -2.0, 2.0] | units.RSun,
hydro_legacy_code,
(100, 100),
base_output_file_name + "_hydro_image.png"
)
hydro_legacy_code.stop()
print("All done!\n")
def merge_two_stars_sph_and_evolve(Mprim, Msec, tcoll, tend):
stars = Particles(2)
stars.mass = [Mprim.value_in(units.MSun),
Msec.value_in(units.MSun)] | units.MSun
stellar_evolution = MESA()
stellar_evolution.particles.add_particles(stars)
# Evolve the stars to tcoll.
while stellar_evolution.model_time < tcoll:
stellar_evolution.evolve_model()
print "Time=", stellar_evolution.model_time, \
stellar_evolution.particles[0].stellar_type, \
stellar_evolution.particles[0].mass, \
stellar_evolution.particles[0].radius, \
stellar_evolution.particles[0].temperature.in_(units.K), \
stellar_evolution.particles[0].luminosity.in_(units.LSun)
print stars
# Convert to SPH particles (nsph per solar mass).
nsph = 100
Nprim = int(nsph*stellar_evolution.particles[0].mass.value_in(units.MSun))
mgas = stellar_evolution.particles[0].mass/Nprim
Nsec = int(stellar_evolution.particles[1].mass/mgas)
print "N gas =", Nprim, Nsec
sph_primary = convert_stellar_model_to_SPH(
stellar_evolution.particles[0],
Nprim,
seed=12345
).gas_particles
sph_secondary = convert_stellar_model_to_SPH(
stellar_evolution.particles[1],
Nsec,
seed=12345
).gas_particles
stellar_evolution.stop()
# Merge the stars using SPH.
distance = 2 | units.RSun
sph_secondary.x += distance
vx = numpy.sqrt(2*constants.G*stars.mass.sum()/distance)
sph_secondary.vx -= vx
print 'distance =', distance, 'vx =', vx.in_(units.kms),
print 'd/v =', (distance/vx).in_(units.hour)
sph_particles = Particles()
sph_particles.add_particles(sph_primary)
sph_particles.add_particles(sph_secondary)
sph_particles.move_to_center()
converter = nbody_system.nbody_to_si(1|units.hour, 1|units.RSun)
hydrodynamics = Gadget2(converter)
hydrodynamics.gas_particles.add_particles(sph_particles)
tf = 10.|units.hour
hydrodynamics.evolve_model(tf)
hydrodynamics.gas_particles.copy_values_of_attributes_to(["x", "y", "z",
"vx", "vy", "vz",
"density",
"u", "pressure"],
sph_particles)
hydrodynamics.stop()
# Convert back to a stellar model.
print "N all =", len(sph_particles)
sph_particles.move_to_center()
clumps = find_clumps(sph_particles, converter)
sph_particles = clumps[0]
print "N blob =", len(sph_particles)
#plot_clumps(clumps)
print "convert SPH to stellar model"
sph_particles.move_to_center()
merged_star = convert_SPH_to_stellar_model(sph_particles)
# Evolve the stellar model.
print "initiate stellar evolution model"
#stellar_evolution = MESA(redirect="none")
stellar_evolution = EVtwin(redirect="none")
stellar_evolution.new_particle_from_model(merged_star, 0.0|units.Myr)
print "star:", stellar_evolution.particles
print "evolve star"
time = [] | units.Myr
mass = [] | units.MSun
radius = [] | units.RSun
temperature = [] | units.K
luminosity = [] | units.LSun
stellar_type = []
while stellar_evolution.model_time < (tend-tcoll):
try:
stellar_evolution.evolve_model()
time.append(stellar_evolution.model_time)
mass.append(stellar_evolution.particles[0].mass)
radius.append(stellar_evolution.particles[0].radius)
temperature.append(stellar_evolution.particles[0].temperature)
luminosity.append(stellar_evolution.particles[0].luminosity)
stellar_type.append(stellar_evolution.particles[0].stellar_type)
print "Time=", time[-1], stellar_type[-1], mass[-1], radius[-1], \
temperature[-1].in_(units.K), luminosity[-1].in_(units.LSun)
if stellar_type[-1] >= 4 | units.stellar_type:
break
except:
print 'Code crashed at time', stellar_evolution.model_time
break
stellar_evolution.stop()
return time, stellar_type, mass, radius, temperature, luminosity
def merge_two_stars_spz_and_evolve(Mprim, Msec, tcoll, tend):
stellar = EVtwin()
stars = Particles(2)
stars[0].mass = Mprim
stars[1].mass = Msec
stellar.particles.add_particle(stars[0])
stellar.particles.add_particle(stars[1])
time = [] | units.Myr
mass = [] | units.MSun
radius = [] | units.RSun
temperature = [] | units.K
luminosity = [] | units.LSun
while stellar.model_time<tcoll:
stellar.evolve_model()
time.append(stellar.model_time)
mass.append(stellar.particles[0].mass)
radius.append(stellar.particles[0].radius)
temperature.append(stellar.particles[0].temperature)
luminosity.append(stellar.particles[0].luminosity)
print "Time=", time[-1], mass[-1], radius[-1], temperature[-1].in_(units.K), luminosity[-1].in_(units.LSun)
n_normal = len(time)
print stars
Nprim = int(100*stellar.particles[0].mass.value_in(units.MSun))
mgas = stellar.particles[0].mass/Nprim
Nsec = int(stellar.particles[1].mass/mgas)
print "N gas=", Nprim, Nsec
sph_primary = convert_stellar_model_to_SPH(
stellar.particles[0],
Nprim,
seed=12345
).gas_particles
sph_secondary = convert_stellar_model_to_SPH(
stellar.particles[0],
Nsec,
seed=12345
).gas_particles
stellar.stop()
distance = 1 | units.RSun
sph_secondary.x += distance
sph_secondary.vx -= 1.7*numpy.sqrt(2*constants.G*stars.mass.sum()/distance)
sph_particles = Particles()
sph_particles.add_particles(sph_primary)
#sph_particles.add_particles(sph_secondary)
sph_particles.move_to_center()
converter = nbody_system.nbody_to_si(1|units.hour, 1|units.RSun)
hydrodynamics = Gadget2(converter)
hydrodynamics.gas_particles.add_particles(sph_particles)
hydrodynamics.evolve_model(10.0|units.hour)
hydrodynamics.gas_particles.copy_values_of_attributes_to(["density", "u", "pressure"],
sph_particles)
hydrodynamics.stop()
print "N all=", len(sph_particles)
clumps = find_clumps(sph_particles, converter)
#sph_particles = clumps[0]
print "N blob=", len(sph_particles)
#plot_clumps(clumps)
#sph_merger = sph_particles[0]
print "convert SPH to stellar model"
merged_star = convert_SPH_to_stellar_model(sph_particles)
#stellar_evolution = MESA()
print "initiate stellar evolution model"
stellar_evolution = EVtwin(redirect="none")
stellar_evolution.new_particle_from_model(merged_star, 0.0|units.Myr)
print "star:", stellar_evolution.particles
print "evolve star"
#stellar_evolution.evolve_model(tend)
while stellar_evolution.model_time<(tend-tcoll):
stellar_evolution.evolve_model()
time.append(stellar_evolution.model_time)
mass.append(stellar_evolution.particles[0].mass)
radius.append(stellar_evolution.particles[0].radius)
temperature.append(stellar_evolution.particles[0].temperature)
luminosity.append(stellar_evolution.particles[0].luminosity)
print "Time=", time[-1], mass[-1], radius[-1], temperature[-1].in_(units.K), luminosity[-1].in_(units.LSun)
print stellar_evolution.particles
stellar_evolution.stop()
return time, mass, radius, temperature, luminosity, n_normal
def head_on_stellar_merger(
masses=[0.3, 3.0] | units.MSun,
star_age=310.0 | units.Myr,
initial_separation=4.0 | units.RSun,
angle=numpy.pi / 3,
initial_speed=3000.0 | units.km / units.s,
initial_speed_perpendicular=30.0 | units.km / units.s,
number_of_sph_particles=50000,
t_end=1.0e4 | units.s,
sph_code=Fi,
):
"""
masses: Mass of the two stars
star_age: Initial age of the stars
number_of_sph_particles: Total number of particles of both stars, divided
according to their masses
t_end: (Physical, not computational) duration of the hydrodynamics
simulation
sph_code: Code to use for the hydrodynamics simulation
"""
# Convert some of the input parameters to string, for use in output file
# names:
n_string = "n" + ("%1.0e" % (number_of_sph_particles)
).replace("+0", "").replace("+", "")
t_end_string = "t" + ("%1.0e" % (t_end.value_in(units.s))
).replace("+0", "").replace("+", "")
base_output_file_name = os.path.join(
get_path_to_results(), "stellar_merger_"+n_string+"_"+t_end_string)
stars = Particles(2)
stars.mass = masses
try:
stellar_evolution = MESA()
stellar_evolution.initialize_code()
except:
print "MESA was not built. Returning."
return
stellar_evolution.commit_parameters()
stellar_evolution.particles.add_particles(stars)
stellar_evolution.commit_particles()
print "Evolving stars with MESA..."
stellar_evolution.evolve_model(star_age)
number_of_sph_particles_1 = int(
round(
number_of_sph_particles
* (
stellar_evolution.particles[0].mass
/ stellar_evolution.particles.mass.sum()
)
)
)
number_of_sph_particles_2 = (
number_of_sph_particles - number_of_sph_particles_1
)
print "Creating initial conditions from a MESA stellar evolution model:"
print(
stellar_evolution.particles[0].mass,
"star consisting of", number_of_sph_particles_1, "particles."
)
sph_particles_1 = convert_stellar_model_to_SPH(
stellar_evolution.particles[0],
number_of_sph_particles_1,
seed=12345
).gas_particles
print(
stellar_evolution.particles[1].mass,
"star consisting of", number_of_sph_particles_2, "particles."
)
sph_particles_2 = convert_stellar_model_to_SPH(
stellar_evolution.particles[1],
number_of_sph_particles_2
).gas_particles
initial_separation += stellar_evolution.particles.radius.sum()
sph_particles_2.x += numpy.cos(angle) * initial_separation
sph_particles_2.y += numpy.sin(angle) * initial_separation
sph_particles_1.vx += numpy.cos(angle) * initial_speed - \
numpy.sin(angle) * initial_speed_perpendicular
sph_particles_1.vy += numpy.cos(angle) * initial_speed_perpendicular + \
numpy.sin(angle) * initial_speed
view = [-0.5, 0.5, -0.5, 0.5] * \
(initial_separation + stellar_evolution.particles.radius.sum())
stellar_evolution.stop()
all_sph_particles = ParticlesSuperset([sph_particles_1, sph_particles_2])
all_sph_particles.move_to_center()
unit_converter = ConvertBetweenGenericAndSiUnits(
1.0 | units.RSun, constants.G, t_end)
hydro_legacy_code = sph_code(unit_converter)
n_steps = 100
hydro_legacy_code.parameters.n_smooth = 96
try:
hydro_legacy_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if "parameter is read-only" not in str(exc):
raise
hydro_legacy_code.gas_particles.add_particles(all_sph_particles)
print "Evolving to t =", t_end, " (using", sph_code.__name__, "SPH code)."
for time, i_step in [(i*t_end/n_steps, i) for i in range(1, n_steps+1)]:
hydro_legacy_code.evolve_model(time)
if not i_step % 4:
hydro_plot(
view,
hydro_legacy_code,
(300, 300),
base_output_file_name +
"_hydro_image{0:=03}.png".format(i_step)
)
hydro_legacy_code.stop()
print "All done!\n"
set_printing_strategy(
"custom", #nbody_converter = converter,
preferred_units=[units.MSun, units.RSun, units.Myr],
precision=11,
prefix="",
separator=" [",
suffix="]")
o, arguments = new_option_parser().parse_args()
print "initialize star"
stellar_evolution = EVtwin()
stellar_evolution.particles.add_particle(Particle(mass=o.Mprim))
stellar_evolution.evolve_model(o.time)
particles = convert_stellar_model_to_SPH(stellar_evolution.particles[0],
500,
seed=12345).gas_particles
stellar_evolution.stop()
from amuse.units.generic_unit_converter import ConvertBetweenGenericAndSiUnits
print "convert star to SPH"
converter = nbody_system.nbody_to_si(1 | units.hour, 1 | units.RSun)
hydrodynamics = Gadget2(converter)
hydrodynamics.gas_particles.add_particles(particles)
hydrodynamics.evolve_model(1.0 | units.s)
hydrodynamics.gas_particles.copy_values_of_attributes_to(
["density", "u", "pressure"], particles)
hydrodynamics.stop()
print "convert SPH to stellar model"
model = convert_SPH_to_stellar_model(particles)
def merge_two_stars_sph_and_evolve(Mprim, Msec, tcoll, tend):
stars = Particles(2)
stars.mass = [Mprim.value_in(units.MSun),
Msec.value_in(units.MSun)] | units.MSun
stellar_evolution = MESA()
stellar_evolution.particles.add_particles(stars)
# Evolve the stars to tcoll.
while stellar_evolution.model_time < tcoll:
stellar_evolution.evolve_model()
print "Time=", stellar_evolution.model_time, \
stellar_evolution.particles[0].stellar_type, \
stellar_evolution.particles[0].mass, \
stellar_evolution.particles[0].radius, \
stellar_evolution.particles[0].temperature.in_(units.K), \
stellar_evolution.particles[0].luminosity.in_(units.LSun)
print stars
# Convert to SPH particles (nsph per solar mass).
nsph = 100
Nprim = int(nsph *
stellar_evolution.particles[0].mass.value_in(units.MSun))
mgas = stellar_evolution.particles[0].mass / Nprim
Nsec = int(stellar_evolution.particles[1].mass / mgas)
print "N gas =", Nprim, Nsec
sph_primary = convert_stellar_model_to_SPH(stellar_evolution.particles[0],
Nprim,
seed=12345).gas_particles
sph_secondary = convert_stellar_model_to_SPH(
stellar_evolution.particles[1], Nsec, seed=12345).gas_particles
stellar_evolution.stop()
# Merge the stars using SPH.
distance = 2 | units.RSun
sph_secondary.x += distance
vx = numpy.sqrt(2 * constants.G * stars.mass.sum() / distance)
sph_secondary.vx -= vx
print 'distance =', distance, 'vx =', vx.in_(units.kms),
print 'd/v =', (distance / vx).in_(units.hour)
sph_particles = Particles()
sph_particles.add_particles(sph_primary)
sph_particles.add_particles(sph_secondary)
sph_particles.move_to_center()
converter = nbody_system.nbody_to_si(1 | units.hour, 1 | units.RSun)
hydrodynamics = Gadget2(converter)
hydrodynamics.gas_particles.add_particles(sph_particles)
tf = 10. | units.hour
hydrodynamics.evolve_model(tf)
hydrodynamics.gas_particles.copy_values_of_attributes_to(
["x", "y", "z", "vx", "vy", "vz", "density", "u", "pressure"],
sph_particles)
hydrodynamics.stop()
# Convert back to a stellar model.
print "N all =", len(sph_particles)
sph_particles.move_to_center()
clumps = find_clumps(sph_particles, converter)
sph_particles = clumps[0]
print "N blob =", len(sph_particles)
#plot_clumps(clumps)
print "convert SPH to stellar model"
sph_particles.move_to_center()
merged_star = convert_SPH_to_stellar_model(sph_particles)
# Evolve the stellar model.
print "initiate stellar evolution model"
#stellar_evolution = MESA(redirect="none")
stellar_evolution = EVtwin(redirect="none")
stellar_evolution.new_particle_from_model(merged_star, 0.0 | units.Myr)
print "star:", stellar_evolution.particles
print "evolve star"
time = [] | units.Myr
mass = [] | units.MSun
radius = [] | units.RSun
temperature = [] | units.K
luminosity = [] | units.LSun
stellar_type = []
while stellar_evolution.model_time < (tend - tcoll):
try:
stellar_evolution.evolve_model()
time.append(stellar_evolution.model_time)
mass.append(stellar_evolution.particles[0].mass)
radius.append(stellar_evolution.particles[0].radius)
temperature.append(stellar_evolution.particles[0].temperature)
luminosity.append(stellar_evolution.particles[0].luminosity)
stellar_type.append(stellar_evolution.particles[0].stellar_type)
print "Time=", time[-1], stellar_type[-1], mass[-1], radius[-1], \
temperature[-1].in_(units.K), luminosity[-1].in_(units.LSun)
if stellar_type[-1] >= 4 | units.stellar_type:
break
except:
print 'Code crashed at time', stellar_evolution.model_time
break
stellar_evolution.stop()
return time, stellar_type, mass, radius, temperature, luminosity
def run_supernova():
# options:
use_hydro_code = Gadget2 # Fi -or- Gadget2
# e.g. dict(use_gl = True) or dict(redirection = "none")
hydro_code_options = dict(number_of_workers=3)
number_of_sph_particles = 30000
t_end = 1.0e5 | units.s
pickle_file = setup_stellar_evolution_model()
print "Creating initial conditions from a MESA stellar evolution model..."
model = convert_stellar_model_to_SPH(
None,
number_of_sph_particles,
seed=12345,
pickle_file=pickle_file,
# base_grid_options = dict(type = "glass", target_rms = 0.01),
with_core_particle=True)
core, gas_without_core, core_radius = \
model.core_particle, model.gas_particles, model.core_radius
if len(core):
print "Created", len(
gas_without_core), "SPH particles and one 'core-particle':\n", core
print "Setting gravitational smoothing to:", core_radius
else:
print "Warning: Only SPH particles created."
inject_supernova_energy(gas_without_core)
print "\nEvolving (SPH) to:", t_end
n_steps = 100
unit_converter = ConvertBetweenGenericAndSiUnits(1.0 | units.RSun,
constants.G, t_end)
hydro_code = use_hydro_code(unit_converter, **hydro_code_options)
try:
hydro_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if "parameter is read-only" not in str(exc):
raise
hydro_code.parameters.epsilon_squared = core_radius**2
hydro_code.parameters.n_smooth_tol = 0.01
hydro_code.gas_particles.add_particles(gas_without_core)
hydro_code.dm_particles.add_particles(core)
times = [] | units.s
potential_energies = [] | units.J
kinetic_energies = [] | units.J
thermal_energies = [] | units.J
for time, i_step in [(i * t_end / n_steps, i)
for i in range(0, n_steps + 1)]:
hydro_code.evolve_model(time)
times.append(time)
potential_energies.append(hydro_code.potential_energy)
kinetic_energies.append(hydro_code.kinetic_energy)
thermal_energies.append(hydro_code.thermal_energy)
hydro_plot([-1.0, 1.0, -1.0, 1.0] * (350 | units.RSun), hydro_code,
(100, 100),
os.path.join(
get_path_to_results(),
"supernova_hydro_image{0:=03}.png".format(i_step)))
energy_plot(
times, kinetic_energies, potential_energies, thermal_energies,
os.path.join(get_path_to_results(), "supernova_energy_evolution.png"))
hydro_code.stop()
print "All done!\n"
def head_on_stellar_merger(
masses = [0.3, 3.0] | units.MSun,
star_age = 310.0 | units.Myr,
maximally_evolved_stars = False,
initial_separation = 4.0 | units.RSun,
angle = numpy.pi / 3,
initial_speed = 3000.0 | units.km / units.s,
initial_speed_perpendicular = 30.0 | units.km / units.s,
number_of_sph_particles = 1000,
t_end = 1.0e4 | units.s,
sph_code = Fi,
steps_per_snapshot = 4,
snapshot_size = 100,
use_stored_stellar_models = True
):
"""
masses: Mass of the two stars
star_age: Initial age of the stars (if maximally_evolved_stars is False)
maximally_evolved_stars: Evolve stars as far as the Stellar Evolution code can get
number_of_sph_particles: Total number of particles of both stars, divided according to their masses
t_end: (Physical, not computational) duration of the hydrodynamics simulation
sph_code: Code to use for the hydrodynamics simulation
steps_per_snapshot: A hydroplot snapshot is generated each time after this many steps (0 or None means no snapshots)
snapshot_size: Size of the snapshot in pixels along one dimension
use_stored_stellar_models: Flag to use previously stored stellar model files (for speed-up).
"""
# Convert some of the input parameters to string, for use in output file names:
n_string = "n" + ("%1.0e"%(number_of_sph_particles)).replace("+0","").replace("+","")
t_end_string = "t" + ("%1.0e"%(t_end.value_in(units.s))).replace("+0","").replace("+","")
masses_string = ("m1_" + ("%0.3e"%(masses[0].value_in(units.MSun))).replace("+0","").replace("+","") +
"_m2_" + ("%0.3e"%(masses[1].value_in(units.MSun))).replace("+0","").replace("+",""))
if maximally_evolved_stars:
star_age_string = "a_max"
else:
star_age_string = "a" + ("%0.3e"%(star_age.value_in(units.Myr))).replace("+0","").replace("+","")
base_output_file_name = os.path.join(get_path_to_results(), "stellar_merger_"+n_string+"_"+t_end_string)
pickle_file_1 = os.path.join(get_path_to_results(), "stellar_merger_"+masses_string+"_"+star_age_string+"_1.pkl")
pickle_file_2 = os.path.join(get_path_to_results(), "stellar_merger_"+masses_string+"_"+star_age_string+"_2.pkl")
if not use_stored_stellar_models or not (os.path.exists(pickle_file_1) and os.path.exists(pickle_file_2)):
stars = Particles(2)
stars.mass = masses
try:
stellar_evolution = MESA()
stellar_evolution.initialize_code()
except:
print "MESA was not built. Returning."
return
stellar_evolution.commit_parameters()
stellar_evolution.particles.add_particles(stars)
stellar_evolution.commit_particles()
if maximally_evolved_stars:
try:
while True:
stellar_evolution.evolve_model()
except AmuseException as exception:
print exception
else:
stellar_evolution.evolve_model(star_age)
if os.path.exists(pickle_file_1):
print "Could not save stellar model 1: file already exists."
else:
pickle_stellar_model(stellar_evolution.particles[0], pickle_file_1)
print "Stellar model 1 saved at:", pickle_file_1
if os.path.exists(pickle_file_2):
print "Could not save stellar model 2: file already exists."
else:
pickle_stellar_model(stellar_evolution.particles[1], pickle_file_2)
print "Stellar model 2 saved at:", pickle_file_2
stellar_evolution.stop()
model_1 = StellarModel2SPH(None, None, pickle_file = pickle_file_1)
model_2 = StellarModel2SPH(None, None, pickle_file = pickle_file_2)
model_1.unpickle_stellar_structure()
model_2.unpickle_stellar_structure()
composition = model_2.composition_profile
midpoints = model_2.midpoints_profile[1:-1]
specific_internal_energy = model_2.specific_internal_energy_profile
number_of_sph_particles_1 = int(round(number_of_sph_particles *
(model_1.mass / (model_1.mass + model_2.mass))))
number_of_sph_particles_2 = number_of_sph_particles - number_of_sph_particles_1
print "Creating initial conditions from a MESA stellar evolution model:"
print model_1.mass, "star consisting of", number_of_sph_particles_1, "particles."
sph_particles_1 = convert_stellar_model_to_SPH(
None,
number_of_sph_particles_1,
seed=12345,
pickle_file = pickle_file_1
).gas_particles
print model_2.mass, "star consisting of", number_of_sph_particles_2, "particles."
sph_particles_2 = convert_stellar_model_to_SPH(
None,
number_of_sph_particles_2,
pickle_file = pickle_file_2
).gas_particles
initial_separation += model_1.radius + model_2.radius
sph_particles_2.x += numpy.cos(angle) * initial_separation
sph_particles_2.y += numpy.sin(angle) * initial_separation
sph_particles_1.vx += numpy.cos(angle) * initial_speed - numpy.sin(angle) * initial_speed_perpendicular
sph_particles_1.vy += numpy.cos(angle) * initial_speed_perpendicular + numpy.sin(angle) * initial_speed
view = [-0.5, 0.5, -0.5, 0.5] * (initial_separation + model_1.radius + model_2.radius)
all_sph_particles = ParticlesSuperset([sph_particles_1, sph_particles_2])
all_sph_particles.move_to_center()
unit_converter = ConvertBetweenGenericAndSiUnits(1.0 | units.RSun, constants.G, t_end)
hydro_legacy_code = sph_code(unit_converter)
n_steps = 100
hydro_legacy_code.parameters.n_smooth = 96
try:
hydro_legacy_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if not "parameter is read-only" in str(exc): raise
hydro_legacy_code.gas_particles.add_particles(all_sph_particles)
times = [] | units.Myr
kinetic_energies = [] | units.J
potential_energies = [] | units.J
thermal_energies = [] | units.J
print "Evolving to:", t_end
for time, i_step in [(i*t_end/n_steps, i) for i in range(1, n_steps+1)]:
hydro_legacy_code.evolve_model(time)
times.append(time)
kinetic_energies.append( hydro_legacy_code.kinetic_energy)
potential_energies.append( hydro_legacy_code.potential_energy)
thermal_energies.append( hydro_legacy_code.thermal_energy)
if steps_per_snapshot and (not i_step % steps_per_snapshot):
hydro_plot(
view,
hydro_legacy_code,
(snapshot_size, snapshot_size),
base_output_file_name + "_hydro_image{0:=03}.png".format(i_step)
)
hydro_legacy_code.gas_particles.new_channel_to(all_sph_particles).copy_attributes(
['mass', 'x','y','z', 'vx','vy','vz', 'u'])
center_of_mass = all_sph_particles.center_of_mass().as_quantity_in(units.RSun)
center_of_mass_velocity = all_sph_particles.center_of_mass_velocity().as_quantity_in(units.km / units.s)
print
print "center_of_mass:", center_of_mass
print "center_of_mass_velocity:", center_of_mass_velocity
all_sph_particles.position -= center_of_mass
sph_midpoints = all_sph_particles.position.lengths()
energy_plot(
times,
kinetic_energies, potential_energies, thermal_energies,
base_output_file_name+"_energy_evolution.png"
)
thermal_energy_plot(
times,
thermal_energies,
base_output_file_name+"_thermal_energy_evolution.png"
)
composition_comparison_plot(
midpoints, composition[0],
sph_midpoints, all_sph_particles.h1,
base_output_file_name+"_composition_h1.png"
)
internal_energy_comparison_plot(
midpoints, specific_internal_energy,
sph_midpoints, all_sph_particles.u,
base_output_file_name+"_new_u.png"
)
hydro_plot(
[-2.0, 2.0, -2.0, 2.0] | units.RSun,
hydro_legacy_code,
(100, 100),
base_output_file_name + "_hydro_image.png"
)
hydro_legacy_code.stop()
print "All done!\n"
def run_supernova():
# options:
use_hydro_code = Gadget2 # Fi -or- Gadget2
# e.g. dict(use_gl = True) or dict(redirection = "none")
hydro_code_options = dict(number_of_workers=3)
number_of_sph_particles = 30000
t_end = 1.0e5 | units.s
pickle_file = setup_stellar_evolution_model()
print "Creating initial conditions from a MESA stellar evolution model..."
model = convert_stellar_model_to_SPH(
None,
number_of_sph_particles,
seed=12345,
pickle_file=pickle_file,
# base_grid_options = dict(type = "glass", target_rms = 0.01),
with_core_particle=True
)
core, gas_without_core, core_radius = \
model.core_particle, model.gas_particles, model.core_radius
if len(core):
print "Created", len(
gas_without_core), "SPH particles and one 'core-particle':\n", core
print "Setting gravitational smoothing to:", core_radius
else:
print "Warning: Only SPH particles created."
inject_supernova_energy(gas_without_core)
print "\nEvolving (SPH) to:", t_end
n_steps = 100
unit_converter = ConvertBetweenGenericAndSiUnits(
1.0 | units.RSun, constants.G, t_end)
hydro_code = use_hydro_code(unit_converter, **hydro_code_options)
try:
hydro_code.parameters.timestep = t_end / n_steps
except Exception as exc:
if "parameter is read-only" not in str(exc):
raise
hydro_code.parameters.epsilon_squared = core_radius**2
hydro_code.parameters.n_smooth_tol = 0.01
hydro_code.gas_particles.add_particles(gas_without_core)
hydro_code.dm_particles.add_particles(core)
times = [] | units.s
potential_energies = [] | units.J
kinetic_energies = [] | units.J
thermal_energies = [] | units.J
for time, i_step in [(i*t_end/n_steps, i) for i in range(0, n_steps+1)]:
hydro_code.evolve_model(time)
times.append(time)
potential_energies.append(hydro_code.potential_energy)
kinetic_energies.append(hydro_code.kinetic_energy)
thermal_energies.append(hydro_code.thermal_energy)
hydro_plot(
[-1.0, 1.0, -1.0, 1.0] * (350 | units.RSun),
hydro_code,
(100, 100),
os.path.join(get_path_to_results(),
"supernova_hydro_image{0:=03}.png".format(i_step))
)
energy_plot(
times, kinetic_energies, potential_energies, thermal_energies,
os.path.join(
get_path_to_results(),
"supernova_energy_evolution.png"
)
)
hydro_code.stop()
print "All done!\n"
