# Concentrated heat flux¶

The Concentrated heat flux boundary condition defines a heat source or a heat sink on a specific node. Note that if this boundary condition type is assigned to an edge, a surface or a volume, this holds for every single node lying on the chosen entity.

Hint

• For positive values the heat flux enters the body, for negative values it represents heat leaving the body.
• Do not use a concentrated heat flux in order to apply distributed heat fluxes, as this may cause undesired heating patterns for meshes with different element sizes and at the boundaries of the assigned entities.