Use the Local Thermal Nonequilibrium multiphysics coupling (
) to account for heat transfer in porous domains where the solid and fluid temperatures are not in equilibrium. This is achieved by coupling the heat equations in the solid and fluid subdomains through a transfer term proportional to the temperature difference between the fluid and the solid. The corresponding heat equations in the solid and in the fluid subdomains read
The fluid velocity is deduced from a porous velocity up, coming, for example, from the Darcy’s law or the Brinkman equations, according to:
The Label is the default multiphysics coupling feature name.
The Name is used primarily as a scope prefix for variables defined by the coupling node. Refer to such variables in expressions using the pattern
<name>.<variable_name>. In order to distinguish between variables belonging to different coupling nodes or physics interfaces, the
name string must be unique. Only letters, numbers, and underscores (_) are permitted in the
Name field. The first character must be a letter.
The default Name (for the first multiphysics coupling feature in the model) is
ltne1.
Select the Heat transfer in solids interface associated to the solid temperature dependent variable. Select the
Heat transfer in fluids interface associated to the fluid temperature-dependent variable.
Enter a Solid volume fraction θp (dimensionless). The default value is 0.5.
Enter a value for the Average pellet radius rp (SI unit: m). Default value is 5e-4 m.
The default Dynamic viscosity μ (SI unit: Pa·s) is used
From material. In the list, choose
User defined to enter another value or expression. When the dynamic viscosity is set in the Heat Transfer in Fluids interface, it also appears in the list.
when the Heat Transfer in Solids interface with
Solid feature is added together with the
Heat Transfer in Fluids interface with
Heat Transfer in Fluids feature.