The Neuman boundary condition constrains the heat flow through the domain boundary walls:
<math>q = -k \frac{\partial T}{\partial n} = q_s </math>
<math>q = -k \frac{\partial T}{\partial n} = -k \mathbf{\hat{n}) } . \nabla T(\mathbf{r}) = q_s </math>
== Electrostatics Analysis==