Imposed velocity or force

This model imposes either the Cartesian or the normal/tangential components of the velocity or force-density vector. The units of the force density will depend on the dimension of the elements in the sub-model domain:

Imposed temperature

This model imposes either a constant value for temperature or a linear function of the coordinates.

Imposed heat flux density

This model adds a contribution to the energy equation that represents the heat flux density on the domain for which the sub-model applies. The units of the heat flux density will depend on the dimension of the elements in the sub-model domain:

Heat conduction problem

This model adds a conductive contribution to the energy equation, to model a conductive wire or plate (usually represented as a PMesh) that is distinct from the material of the domain itself.

Pointwise velocity imposed

This model imposes the velocity at one point through a penalty formulation.

Coordinates imposed

This model fixes any component of the coordinates on a sub-model domain. This sub-model allows you to forbid partial or total deformation on a part of a domain subject to remeshing.

Diffuse gray wall imposed

This model specifies that a fraction of the incident radiative energy is dissipated as heat in the boundary, another fraction passes through the boundary, and the rest is reflected. The diffuse gray wall boundary condition is only available when modeling internal radiation (see Internal Radiation).

Porous jump model

This model can be selected to represent a thin, rigid membrane that is porous (for example, a filter), which allows fluid to pass through but is associated with a drop in the pressure. The constitutive equation of the porous jump sub-model relates the pressure drop () to the normal velocity component (), and is given by:

(8–17)

where is the thickness of the rigid membrane, is the reference viscosity, and is a function that represents the temperature dependence of the viscosity. is the membrane permeability, and has units of (where is the units for length). Since various membranes can be defined, the material parameters are stored in a local database. See Defining a Material Dataset for further details.