IcyDwarf v14.11.1

Thermal: Fixed treatment of convection in porous media. The formula for
the Rayleigh number for hydrothermal circulation, taken from Desch et
al. (2009), was valid for fluids but not for porous media. The new,
appropriate formula for Ra is taken from Nield (1997).
Moreover, the value of the thermal conductivity kap1 previously used in
the calculation of Ra was, erroneously, the enhanced effective thermal
conductivity of hydrothermal circulation. It is now the actual thermal
conductivity of the lowest cracked layer.
IcyDwarf v14.11.1

Thermal: Fixed treatment of convection in hydrothermal layers.
The Ra number was previously taken from Desch et al. (2009). This is
appropriate for convection in fluids, but not in porous media. Ra is now
calculated according to Nield (1997).
Moreover, the thermal conductivity kap1 in the Ra calculation was
previously taken as the enhanced effective thermal conductivity due to
convection. Is is now taken as the actual thermal conductivity of the
lowest cracked layer.