dt = 100.0
if (ca.velocity().max()>1.0e-7):
dt = float(0.5*smallest_size/ca.velocity().max())
if (max_dt < dt):
dt = max_dt
it.command("solve time {}".format(dt))
it.command("cfd update")
cfd_link.send_data(dt) # solve interval
new_porosity = ca.porosity()
cfd_link.send_data(old_porosity*(1-r_factor)+new_porosity*r_factor)
old_porosity = new_porosity
new_force = (ca.drag().T/element_volume).T/fluid_density
cfd_link.send_data(old_force*(1-r_factor)+new_force*r_factor)
old_force = new_force
ca.set_pressure(cfd_link.read_data())
ca.set_pressure_gradient(cfd_link.read_data())
time += dt
newu = cfd_link.read_data()
ca.set_velocity(oldu*(1-r_factor)+newu*r_factor)
oldu = newu
cfd_link.send_data(0.0) # solve interval
cfd_link.close()
del cfd_link
it.command("history write 1,2 file 'fluidized_bed_4.txt' truncate")
set gravity 0 0 -9.81
def fluid_time
global fluid_time = mech.age
end
ball history id 1 zvelocity id 1
history add id 2 fish @fluid_time
plot clear
plot add hist 1 vs 2
plot add cfdelement shape arrow colorby vectorattribute "velocity"
""".format(fluid_density, fluid_viscosity))
element_volume = ca.volume()
dt = 0.005
for i in range(100):
it.command("solve age {}".format(it.mech_age()+dt))
print "sending solve time"
cfd_link.send_data(dt) # solve interval
cfd_link.send_data(ca.porosity())
cfd_link.send_data((ca.drag().T/element_volume).T/fluid_density)
print " cfd solve started"
ca.set_pressure(cfd_link.read_data())
ca.set_pressure_gradient(cfd_link.read_data())
ca.set_velocity(cfd_link.read_data())
print " cfd solve ended"
cfd_link.send_data(0.0) # solve interval
print "ball z velocity", it.ball.find(1).vel_z()
n=ca.porosity()
cfd_link.send_data(n)
ca.set_extra(1, np.zeros(it.element.cfd.count()))
ca.set_extra(2, np.zeros(it.element.cfd.count()))
ca.set_extra(3, np.zeros((it.element.cfd.count(),3)))
for b in it.ball.cfd.list():
for e,v in zip(b.elements(), b.overlaps()):
e.set_extra(1, e.extra(1)+v*b.ball().radius())
e.set_extra(2, e.extra(2)+v)
e.set_extra(3, e.extra(3)+v*b.ball().vel())
dbar = 2*ca.extra(1)/ca.extra(2)
ubar = (ca.extra(3).T/ca.extra(2)).T
du = np.linalg.norm(ubar.T - ca.velocity().T,axis=0)
re = (du*fluid_density*dbar/fluid_viscosity).T
beta = fluid_viscosity*(1-n)/dbar**2/n*(150*(1-n)+1.75*re)/fluid_density
#print beta, ubar
new_force = (ca.drag().T/element_volume).T/fluid_density
cfd_link.send_data(beta)
cfd_link.send_data(ubar)
print " cfd solve started"
ca.set_pressure(cfd_link.read_data())
ca.set_pressure_gradient(cfd_link.read_data())
newu = cfd_link.read_data()
ca.set_velocity(oldu*(1-r_factor)+newu*r_factor)
oldu = newu
print " cfd solve ended"
cfd_link.send_data(0.0)
it.command('plot bitmap filename "simple_porous1.png"')
ball prop kn 1e2 ks 1e2 fric 0.25
set gravity 0 0 -9.81
def fluid_time
global fluid_time = mech.age
end
ball history id 1 zvelocity id 1
history add id 2 fish @fluid_time
plot clear
plot add hist 1 vs 2
plot add cfdelement shape arrow colorby vectorattribute "velocity"
""".format(fluid_density, fluid_viscosity))
element_volume = ca.volume()
dt = 0.005
for i in range(100):
it.command("solve age {}".format(it.mech_age() + dt))
print "sending solve time"
cfd_link.send_data(dt) # solve interval
cfd_link.send_data(ca.porosity())
cfd_link.send_data((ca.drag().T / element_volume).T / fluid_density)
print " cfd solve started"
ca.set_pressure(cfd_link.read_data())
ca.set_pressure_gradient(cfd_link.read_data())
ca.set_velocity(cfd_link.read_data())
print " cfd solve ended"
cfd_link.send_data(0.0) # solve interval
print "ball z velocity", it.ball.find(1).vel_z()