def __init__(self, dim, dt, dx, L,
D_rho, mu, walls):
self.dim = dim
self.dt = dt
self.dx = dx
self.L = L
self.D_rho = D_rho
self.mu = mu
self.walls = walls
self.i = 0
self.t = 0.0
nx = int(round((self.L / self.dx)))
self.dx = L / nx
if self.dim == 1:
self.mesh = PeriodicGrid1D(dx=np.array([self.dx]), nx=nx)
elif self.dim == 2:
self.mesh = PeriodicGrid2D(dx=np.array([self.dx]),
dy=np.array([self.dx]), nx=nx, ny=nx)
self.L_perturb = self.L
eps = 1e-2
x = self.get_x()
if self.dim == 1:
perturb = eps * np.sin(2.0 * np.pi * x / self.L_perturb)
else:
X, Y = np.meshgrid(x, x)
perturb = eps * np.sin(2.0 * np.pi * X * Y / self.L_perturb ** 2)
rho_init = 1.0 + perturb
c_init = 1.0 + perturb
if self.walls is not None:
rho_init *= np.logical_not(self.walls.a)
c_init *= np.logical_not(self.walls.a)
mask = make_mask(self.mesh, self.walls)
self.D_rho_var = fipy.FaceVariable(mesh=self.mesh,
value=self.D_rho)
self.D_rho_var.setValue(0.0, where=mask)
self.D_c_var = fipy.FaceVariable(mesh=self.mesh, value=1.0)
self.D_c_var.setValue(0.0, where=mask)
else:
self.D_rho_var = self.D_rho
self.D_c_var = 1.0
self.rho = fipy.CellVariable(mesh=self.mesh, value=rho_init.T.ravel())
self.c = fipy.CellVariable(mesh=self.mesh, value=c_init.T.ravel())
eq_rho = (TransientTerm(var=self.rho) ==
DiffusionTerm(coeff=self.D_rho_var, var=self.rho) -
ConvectionTerm(coeff=mu * self.c.grad, var=self.rho))
eq_c = (TransientTerm(var=self.c) ==
DiffusionTerm(coeff=self.D_c_var, var=self.c) +
self.rho -
ImplicitSourceTerm(coeff=1.0, var=self.c))
self.eq = eq_rho & eq_c
D = 1.0
n = 1000
nx = int(round(L / dx))
mesh = PeriodicGrid2D(dx=np.array([dx]), dy=np.array([dx]), nx=nx, ny=nx)
phi = fipy.CellVariable(mesh=mesh, value=0.0)
maze = bannock.walls.Maze(L, dim=2, dx=dx, d=dx, seed=None)
maze_ravel = maze.a.T.ravel()
phi0 = np.random.uniform(0.0, 1.0, size=maze_ravel.shape)
phi0 *= np.logical_not(maze_ravel)
print(phi0)
phi.setValue(phi0)
mask = make_mask(mesh, maze)
mask_D = fipy.FaceVariable(mesh=mesh, value=D)
mask_D.setValue(0.0, where=mask)
eq = fipy.TransientTerm() == fipy.DiffusionTerm(coeff=mask_D)
viewer = fipy.Matplotlib2DViewer(vars=phi, colorbar=None)
viewer.plotMesh()
for step in range(n):
eq.solve(var=phi, dt=dt)
viewer.plot()
print(step)
raw_input()
