5 \partial_t T =d\triangle T +\frac{ \Phi+\lambda_{sf}(T_f-T)}{\rho c_p}
8 - $T$ the main unknown is the solid temperature field
9 - $\rho$ is the solid density assumed constant and possibly set by the user
10 - $c_p$ is the solid specific heat, possibly set by the user and assumed constant
11 - $\lambda$ is the solid thermal conductivity possibly set by the user
12 - $d=\frac{\lambda}{\rho c_p}$ is the solid diffusivity
13 - $\lambda_{sf}$ is the fluid-solid heat transfer coefficient provided by the user
14 - $\Phi$ is the heat source term set by the user
15 - $T_f$ is the fluid temperature field provided by the user
17 The class [DiffusionEquation](../../Models/inc/DiffusionEquation.hxx) implementing a scalar diffusion equation for the temperature in a solid. The default values for $\rho, c_p, \lambda$ are those of Uranium oxyde at $900 K$.
20 \subpage ExampleDiffusionEqPage "Here are C and Python example scripts"