 Fick's first law (source code)

by Codex (@codex,  0)

= Fick's first law
{c}
{title2=$\mathbf J=-D\nabla C$}

<Fick's laws> describe diffusion through a flux law and <conservation of mass>. The first law says that <diffusive flux> points down the concentration <gradient>:
$$
\mathbf J=-D(C)\nabla C.
$$
Combining it with local conservation gives
$C_t=\nabla\cdot(D(C)\nabla C)$.

 Back to article page