def get_equations(self):
from pysph.sph.equation import Group
from pysph.sph.basic_equations import (ContinuityEquation,
MonaghanArtificialViscosity,
XSPHCorrection,
VelocityGradient2D)
from pysph.sph.solid_mech.basic import (IsothermalEOS,
MomentumEquationWithStress,
HookesDeviatoricStressRate,
MonaghanArtificialStress)
equations = []
g1 = []
all = self.solids + self.elastic_solids
for elastic_solid in self.elastic_solids:
g1.append(
# p
IsothermalEOS(elastic_solid, sources=None))
g1.append(
# vi,j : requires properties v00, v01, v10, v11
VelocityGradient2D(dest=elastic_solid, sources=all))
g1.append(
# rij : requires properties r00, r01, r02, r11, r12, r22,
# s00, s01, s02, s11, s12, s22
MonaghanArtificialStress(dest=elastic_solid,
sources=None,
eps=self.artificial_stress_eps))
equations.append(Group(equations=g1))
g2 = []
for elastic_solid in self.elastic_solids:
g2.append(ContinuityEquation(dest=elastic_solid, sources=all), )
g2.append(
# au, av
MomentumEquationWithStress(dest=elastic_solid, sources=all), )
g2.append(
# au, av
MonaghanArtificialViscosity(dest=elastic_solid,
sources=all,
alpha=self.alpha,
beta=self.beta), )
g2.append(
# a_s00, a_s01, a_s11
HookesDeviatoricStressRate(dest=elastic_solid, sources=None), )
g2.append(
# ax, ay, az
XSPHCorrection(dest=elastic_solid,
sources=[elastic_solid],
eps=self.xsph_eps), )
equations.append(Group(g2))
return equations
def create_equations(self):
equations = [
# update smoothing length
# Group(
# equations = [
# UpdateSmoothingLengthFromVolume(dest='plate', sources=['plate', 'projectile'], dim=dim, k=hdx),
# UpdateSmoothingLengthFromVolume(dest='projectile', sources=['plate', 'projectile'], dim=dim, k=hdx),
# ],
# update_nnps=True,
# ),
# compute properties from the current state
Group(equations=[
# EOS (compute the pressure using one of the EOSs)
# MieGruneisenEOS(dest='plate', sources=None, gamma=gamma1, r0=ro1 , c0=C1, S=S1),
# MieGruneisenEOS(dest='projectile', sources=None, gamma=gamma2, r0=ro2 , c0=C2, S=S2),
StiffenedGasEOS(
dest='plate', sources=None, gamma=gamma1, r0=ro1, c0=C1),
StiffenedGasEOS(dest='projectile',
sources=None,
gamma=gamma2,
r0=ro2,
c0=C2),
# compute the velocity gradient tensor
VelocityGradient3D(dest='plate', sources=['plate']),
VelocityGradient3D(dest='projectile', sources=['projectile']),
# # stress
VonMisesPlasticity2D(
dest='plate', sources=None, flow_stress=Yo1),
VonMisesPlasticity2D(
dest='projectile', sources=None, flow_stress=Yo2),
# # artificial stress to avoid clumping
MonaghanArtificialStress(dest='plate', sources=None, eps=0.3),
MonaghanArtificialStress(
dest='projectile', sources=None, eps=0.3),
]),
# accelerations (rho, u, v, ...)
Group(equations=[
# continuity equation
ContinuityEquation(dest='plate',
sources=['projectile', 'plate']),
ContinuityEquation(dest='projectile',
sources=['projectile', 'plate']),
# momentum equation
MomentumEquationWithStress(dest='projectile',
sources=[
'projectile',
'plate',
]),
MomentumEquationWithStress(dest='plate',
sources=[
'projectile',
'plate',
]),
# energy equation:
EnergyEquationWithStress(dest='plate',
sources=[
'projectile',
'plate',
],
alpha=avisc_alpha,
beta=avisc_beta,
eta=avisc_eta),
EnergyEquationWithStress(dest='projectile',
sources=[
'projectile',
'plate',
],
alpha=avisc_alpha,
beta=avisc_beta,
eta=avisc_eta),
# avisc
MonaghanArtificialViscosity(dest='plate',
sources=['projectile', 'plate'],
alpha=avisc_alpha,
beta=avisc_beta),
MonaghanArtificialViscosity(dest='projectile',
sources=['projectile', 'plate'],
alpha=avisc_alpha,
beta=avisc_beta),
# updates to the stress term
HookesDeviatoricStressRate(
dest='plate', sources=None, shear_mod=1.),
HookesDeviatoricStressRate(
dest='projectile', sources=None, shear_mod=1.),
# position stepping
XSPHCorrection(dest='plate', sources=['plate'], eps=xsph_eps),
XSPHCorrection(
dest='projectile', sources=['projectile'], eps=xsph_eps),
]),
] # End Group list
return equations
def create_equations(self):
equations = [
# Properties computed set from the current state
Group(
equations=[
# p
IsothermalEOS(dest='solid',
sources=None,
rho0=rho0,
c0=c0,
p0=0.0),
# vi,j : requires properties v00, v01, v10, v11
VelocityGradient2D(dest='solid', sources=[
'solid',
]),
# rij : requires properties r00, r01, r02, r11, r12, r22,
# s00, s01, s02, s11, s12, s22
MonaghanArtificialStress(dest='solid',
sources=None,
eps=0.3),
], ),
# Acceleration variables are now computed
Group(equations=[
# arho
ContinuityEquation(dest='solid', sources=[
'solid',
]),
# au, av
MomentumEquationWithStress(dest='solid',
sources=[
'solid',
],
n=4,
wdeltap=self.wdeltap),
# au, av
MonaghanArtificialViscosity(dest='solid',
sources=[
'solid',
],
alpha=1.0,
beta=1.0),
# a_s00, a_s01, a_s11
HookesDeviatoricStressRate(dest='solid',
sources=None,
shear_mod=G),
# ax, ay, az
XSPHCorrection(dest='solid', sources=[
'solid',
], eps=0.5),
]) # End Acceleration Group
] # End Group list
return equations