Error MessageIncorrect Emissivity andor Transmissivity Values


A radiation analysis stops with one (or more) of the following errors:

Error: The emissivity > 1

Error: The emissivity < 0

Error: The transmissivity > 1

Error: The transmissivity < 0

Error: The sum of the emissivity and transmissivity > 1



By definition, the emissivity and transmissivity terms must be between 0 and 1, and their values must sum to 1.0 or less.


  • Emissivity is a measure of how much radiative energy can be absorbed and emitted by an object.
  • Transmissivity is a measure of how much radiative energy can pass through an object. 

Both are properties that are assigned to solids materials. However, emissivity can also be assigned to a fluid material, where it is automatically applied to the wetted solid surfaces and wall surfaces of that fluid. Transmissivity can only be assigned to solids.

To resolve this issue, adjust the values of emissivity and/or transmissivity to ensure that they are between 0 and 1 and that their sum does not exceed 1.0.





Simulation CFD