def testPastCylinder():
n = 20 # width - 0x
m = 40 # length - 0y
rho = 1. # density
v = 0.03
tau = v * 3. + 0.5 # relaxation time
t_f = 500 # final time
u = 0.3
reynolds = str(m * u / v)
solid = np.zeros((m, n))
# circle
radius = 6
x0 = 20
y0 = m / 2
for i in range(0, n):
for j in range(0, m):
if (j - y0)**2 + (i - x0)**2 <= radius**2:
solid[j, i] = 1
userGrid = gd.Grid(n, m)
bc = flow_past_cylinder(userGrid, u, rho)
lat_bol = lb.D2Q9(grid=userGrid,
iterations=t_f,
relaxation_time=tau,
boundary=bc,
solid_cells=solid,
plot_velocity=False)
def testPressurePressurePipe():
n = 50 # length - 0x
m = 300 # height - 0y
v = 0.1 # viscosity
p_left = 2. / 1. # left pressure
p_right = 1. / 1. # right pressure
t_f = 500 # final time
tau = v * 3. + 0.5
user_grid = gd.Grid(width=m, height=n)
bc = pipe_pp_bc(grid=user_grid, p_right=p_right, p_left=p_left)
lat_bol = lb.D2Q9(grid=user_grid,
iterations=t_f,
boundary=bc,
relaxation_time=tau,
plot_velocity=False)
def testVelocityVelocityPipe():
n = 50 # length - 0x
m = 300 # height - 0y
v = 0.1 # viscosity
v_left = 1. / 10. # left velocity
v_right = 1. / 10. # right pressure
t_f = 500 # final time
tau = v * 3. + 0.5
user_grid = gd.Grid(width=m, height=n)
# boundary conditions
bc = pipe_vv_bc(grid=user_grid, v_right=v_right, v_left=v_left)
lat_bol = lb.D2Q9(grid=user_grid,
iterations=t_f,
boundary=bc,
relaxation_time=tau,
plot_velocity=False)
def testDrivenCavity(self):
n = 100 # width - 0x
m = 100 # length - 0y
v = 0.1 # viscosity
tau = v * 3. + 0.5 # relaxation time
t_f = 500 # final time
u_x = 0.1
user_grid = gd.Grid(n, m)
reynolds = n * u_x / v
self.assertEqual(reynolds, n)
bc = driven_cavity_boundaries(user_grid, u_x)
lat_bol = lb.D2Q9(grid=user_grid,
iterations=t_f,
boundary=bc,
relaxation_time=tau,
plot_velocity=False)
def testPoiseuilleFlowPeriodicZeroVelocities():
n = 100 # width - 0x
m = 30 # height - 0y
v = 0.1 # viscosity
tau = v * 3. + 0.5 # relaxation time
t_f = 500 # final time
g = 1e-5
gravity = gd.LatticeVelocity(g, 0) # acceleration by gravity
userGrid = gd.Grid(n, m)
bc = horizontal_poiseuille_boundaries_zero_v(grid=userGrid)
lat_bol = lb.D2Q9(grid=userGrid,
iterations=t_f,
relaxation_time=tau,
ext_force=gravity,
boundary=bc,
plot_velocity=False)
def start_driven_cavity(self, entries):
print entries
n = entries[2][1] # width - 0x
m = entries[2][1] # length - 0y
v = entries[1][1] # viscosity
tau = self.calc_tau(v)
t_f = 301 # final time
u_x = entries[0][1]
reynolds = n * u_x / v
velocity = gd.LatticeVelocity(u_x, 0)
user_grid = gd.Grid(n, m)
# boundary conditions
bc = self.driven_cavity_boundaries(user_grid, velocity)
lat_bol = lb.D2Q9(grid=user_grid,
iterations=t_f,
boundary=bc,
relaxation_time=tau,
reynolds=reynolds)
def start_pipe_flow(self, entries):
print entries
n = entries[4][1] # width - 0x
m = entries[3][1] # length - 0y
v = entries[2][1] # viscosity
t_f = entries[5][1] # final time
tau = v * 3. + 0.5
u_x = entries[0][1]
p = entries[1][1]
reynolds = n * u_x / v
user_grid = gd.Grid(n, m)
# print isinstance(velocity,lv.LatticeVelocity)
# boundary conditions
bc = self.pipe_vp_bc(grid=user_grid, v_left=u_x, p_right=p)
lat_bol = lb.D2Q9(grid=user_grid,
iterations=t_f,
boundary=bc,
relaxation_time=tau,
reynolds=reynolds)
path = os.path.dirname(
os.path.abspath(inspect.getfile(inspect.currentframe())))
ps.save_all(lat_bol, path=path)
ps.plot_streamlines(lat_bol, path=path)
def __init__(self,
grid=None,
iterations=1000,
eps=None,
check_convergence=False,
solid_cells=None,
relaxation_time=None,
density=None,
ext_force=None,
boundary=None,
reynolds=None,
plot_velocity=True,
plot_streamlines=True,
path=None):
global Q, D, e, w, c, c_s2, dt
w = self.initialize_weights()
e = self.initialize_normal_velocities()
self.iterations = iterations
self.grid = (grid, gd.Grid(10, 10))[grid is None]
self.solid = (solid_cells, np.zeros(
(self.grid.height, self.grid.width)))[solid_cells is None]
self.bc = (boundary, gd.default_poiseuille_boundaries(
self.grid))[boundary is None]
self.tau = (relaxation_time,
1)[relaxation_time is None] # short 'if-else' statement
self.initial_density = (density, 1)[density is None]
self.applied_force = (ext_force,
gd.LatticeVelocity(0., 0.))[ext_force is None]
self.viscosity = (1. / 3.) * (self.tau - 0.5)
self.reynolds = (reynolds, 0)[reynolds is None]
self.f, self.u, self.rho = self.initialize(self.grid.width,
self.grid.height)
self.stream = np.zeros((self.grid.height, self.grid.width))
self.vorticity = np.zeros((self.grid.height, self.grid.width))
if path is None:
path = os.path.dirname(
os.path.abspath(inspect.getfile(inspect.currentframe())))
title = ''
# elapsed_time=0
start = timer()
if check_convergence:
self.iterations = 0
eps = (eps, 1e-8)[eps is None]
while True:
ux_temp = np.copy(self.u.x)
uy_temp = np.copy(self.u.y)
rho_temp = np.copy(self.rho)
mv.compute_macroscopic(self, e)
if (self.applied_force.x != 0) | (self.applied_force.y != 0):
self.external_force()
if self.converge(ux=ux_temp, uy=uy_temp, rho=rho_temp,
eps=eps):
if self.iterations > 100:
break
self.collision_step()
self.streaming_step()
self.boundary_conditions()
if (self.iterations % 50 == 0) & (self.iterations > 0):
print(self.iterations)
title = "Re_" + str(self.reynolds) + "_vis_" + str(self.viscosity) + \
"_grid_" + str(self.grid.width) + 'x' + str(self.grid.height) + '_t_' + str(self.iterations)
if plot_streamlines:
if self.iterations % 500 == 0:
ps.plot_streamlines(self,
title=title,
path=path,
save=True)
if plot_velocity:
ps.plot_ux(self, title=title, path=path)
ps.plot_uy(self, title=title, path=path)
self.iterations += 1
print self.iterations
else:
for i in range(0, self.iterations + 1):
mv.compute_macroscopic(self, e)
if (self.applied_force.x != 0) | (self.applied_force.y != 0):
self.external_force()
self.collision_step()
self.streaming_step()
self.boundary_conditions()
if (i % 50 == 0) & (i > 0):
print(i)
title = "Re_" + str(self.reynolds) + "_vis_" + str(self.viscosity) + \
"_grid_" + str(self.grid.width) + 'x' + str(self.grid.height) + '_t_' + str(i)
if plot_streamlines:
if i % 500 == 0:
ps.plot_streamlines(self,
title=title,
path=path,
save=True)
if plot_velocity:
ps.plot_ux(self, title=title, path=path)
ps.plot_uy(self, title=title, path=path)
elapsed_time = timer() - start
print(str(elapsed_time) + " sec.")
return False
def velocity_stream_and_vorticity(self):
# todo return vorticity and stream, save them
u = np.array(self.u.x)
v = np.array(self.u.y)
int_u_x = it.simps(u, axis=1)
int_u_y = it.simps(u, axis=0)
int_v_x = it.simps(v, axis=1)
int_v_y = it.simps(v, axis=0)
self.stream = int_u_y[
np.newaxis, :] - int_v_x[:, np.newaxis] # stream function (psi)
self.vorticity = int_u_x[:, np.newaxis] + int_v_y[
np.newaxis, :] # vorticity
if __name__ == "__main__":
n = 30 # width - lx
m = 60 # height - ly
t = 500 # final time
gravity = gd.LatticeVelocity(0, 1e-8) # acceleration by gravity
solid = np.zeros((Q, n, m))
userGrid = gd.Grid(n, m)
lat_bol = D2Q9(grid=userGrid,
iterations=t,
ext_force=gravity,
plot_velocity=False,
plot_streamlines=False)
ps.plot_poiseuille_solution_0x(lat_bol)
assert isinstance(p_right, float), "Incorrect type"
assert isinstance(p_left, float), "Incorrect type"
for i in range(0, grid.width):
boundaries.append(gd.Boundary(grid.top_faces[i], 'zoe_he_velocity', value=u))
boundaries.append(gd.Boundary(grid.bottom_faces[i], 'zoe_he_velocity', value=u))
for i in range(0, grid.height):
boundaries.append(gd.Boundary(grid.left_faces[i], 'zoe_he_pressure', value=p_left))
boundaries.append(gd.Boundary(grid.right_faces[i], 'zoe_he_pressure', value=p_right))
return boundaries
if __name__ == "__main__":
n = 30 # length - 0x
m = 200 # height - 0y
v = 0.1 # viscosity
p_left = 2. / 1. # left pressure
p_right = 1. / 1. # right pressure
t_f = 500 # final time
tau = v * 3. + 0.5
user_grid = gd.Grid(width=m, height=n)
# boundary conditions
bc = pipe_pp_bc(grid=user_grid, p_right=p_right, p_left=p_left)
lat_bol = lb.D2Q9(grid=user_grid,
iterations=t_f,
boundary=bc,
relaxation_time=tau)
path = os.path.dirname(os.path.abspath(inspect.getfile(inspect.currentframe())))
print(path)
ps.save_all(lat_bol,path=path)
ps.plot_streamlines(lat_bol, path=path)
