def blocks(self):
dx = ufl.Measure("dx", self.mesh)
u, p = self.uu_[0:2]
v, q = self.vv_[0:2]
aa = [[
ufl.inner(self.sigma(u), symgrad(v)) * dx,
ufl.inner(p, v) * dx
], [ufl.inner(q, u) * dx, 0]]
# Notice that dot(sigma(Eps), symgrad(v)) = dot(Eps, sigma(symgrad(v)))
ff = [-ufl.inner(self.Eps, self.sigma(v)) * dx, 0]
return [aa, ff]
def sigma_law(u):
return lame[0] * ufl.nabla_div(u) * ufl.Identity(
2) + 2 * lame[1] * symgrad(u)
def sigma(u):
return lamb * ufl.nabla_div(u) * df.Identity(2) + 2 * mu * symgrad(u)