| Abstract: | ![]()
Complete thermodynamic evaluation of energy conversion devices calls for energy and entropy balance equations. While the subject of radiation energy has been well taken care of, the same is not true for the entropy of radiation. This has become obvious from the discussion about the maximum work that can be drawn from solar radiation. This article collects and reflects the basic equations needed to calculate the radiation entropy, and it discusses the influence of the three major input functions on the entropy, namely the spectral and hemispherical distribution of radiation intensity, and its degree of polarization. Results of realistic calculations using atmospheric models are given in the last section in form of an energy-entropy diagram. |
