Erik Kostson
Ansys Employee
This is not a volumetric heat load.

These are heat flow rates. These are concentrated nodal loads, and are used mainly in line-element models (conducting bars, convection links, etc.) where you cannot specify convections and heat fluxes. A positive value of heat flow rate indicates heat flowing into the node (that is, the element gains heat)

For more info on this and thermal boundary conditions and loads, see the help manual (Apdl), and chapter 2 (thermal analysis), 2.5. Applying Loads and Obtaining the Solution.

All the best