Use this node to model inflow of heat through a virtual domain, at inlet boundaries of non-solid domains. The upstream temperature Tustr and upstream absolute pressure pustr are known at the outer boundary of the virtual domain. The inflow condition is often similar to a temperature condition. However using this condition the upstream temperature is not strictly enforced at the inlet. The higher the flow rate, the smallest difference between the inlet temperature and upstream temperature. In case of heat sources or temperature constraints close to the inlet boundary, the inflow condition induces a temperature profile that approaches to the temperature profile that would be obtained by computing the solution in the virtual domain upstream the inlet.

where ΔH is the sensible enthalpy. See Theory for the Inflow Boundary Condition for the definition of ΔH and more details on the Danckwerts condition.

The Upstream temperature Tustr should be specified. For User Defined, enter a value or expression. Else, select any available input (like Ambient temperature defined in an Ambient Properties node under Definitions).

Select the Specify upstream absolute pressure check-box to set a different value than the absolute inlet pressure for the Upstream absolute pressure pustr, and take into account work done by pressure forces in the expression of the enthalpy. For User Defined, enter a value or expression. Else, select an Ambient absolute pressure defined in an Ambient Properties node under Definitions.

Physics tab with interface as Heat Transfer in Solids and Fluids, or any version of the Heat Transfer interface selected:

Physics tab with Porous Medium>Fluid selected in the model tree: