#import the appropriate ESyS-Particle modules:
from esys.lsm import *
from esys.lsm.util import Vec3, BoundingBox
#instantiate a simulation object
#and initialise the neighbour search algorithm:
sim = LsmMpi(numWorkerProcesses=1, mpiDimList=[1,1,1])
sim.initNeighbourSearch(
particleType="NRotSphere",
gridSpacing=2.5,
verletDist=0.5
)
#set the number of timesteps and timestep increment:
sim.setNumTimeSteps(10000)
sim.setTimeStepSize(0.001)
#specify the spatial domain for the simulation:
domain = BoundingBox(Vec3(-20,-20,-20), Vec3(20,20,20))
sim.setSpatialDomain(domain)
#add the first particle to the domain:
particle=NRotSphere(id=0, posn=Vec3(-5,5,-5), radius=1.0, mass=1.0)
particle.setLinearVelocity(Vec3(1.0,-1.0,1.0))
sim.createParticle(particle)
#add the second particle to the domain:
particle=NRotSphere(id=1, posn=Vec3(5,5,5), radius=1.5, mass=2.0)
particle.setLinearVelocity(Vec3(-1.0,-1.0,-1.0))
sim.createParticle(particle)
#specify the type of interactions between colliding particles:
sim.createInteractionGroup(
NRotElasticPrms(
name = "elastic_repulsion",
normalK = 10000.0,
scaling = True
Example #2
0
sim.initNeighbourSearch(
    particleType="NRotSphere",
    gridSpacing=0.2,
    verletDist=0.1
)

# set the number of timesteps and timestep increment:
sim.setNumTimeSteps(5000000)
sim.setTimeStepSize(0.0001)
L = 10
Ld = L + 1
kT = 0.1
a = sqrt(kT)

# specify the spatial domain for the simulation:
domain = BoundingBox(Vec3(-Ld, -Ld, -Ld), Vec3(Ld, Ld, Ld))
sim.setSpatialDomain(
    bBox=domain, circDimList=[False, False, False])
# add a cube of particles to the domain:
#cube = CubicBlock(dimCount=[20, 20, 20], radius=0.05)
#sim.createParticles(cube)
N = 100
seed(1234)
for n in range(N):
    p = NRotSphere(id=n, posn=uniform(), radius=0.05, mass=1.0)
    sim.createParticle(p)

for n in range(sim.getNumParticles()):
    sim.setParticleVelocity(
        id=n,
        Velocity=Vec3(a*randn(), a*randn(), a*randn()))