International Journal of Biometeorology

, Volume 54, Issue 2, pp 131–139 | Cite as

Modelling radiation fluxes in simple and complex environments: basics of the RayMan model

Original Paper


Short- and long-wave radiation flux densities absorbed by people have a significant influence on their energy balance. The heat effect of the absorbed radiation flux densities is parameterised by the mean radiant temperature. This paper presents the physical basis of the RayMan model, which simulates the short- and long-wave radiation flux densities from the three-dimensional surroundings in simple and complex environments. RayMan has the character of a freely available radiation and human-bioclimate model. The aim of the RayMan model is to calculate radiation flux densities, sunshine duration, shadow spaces and thermo-physiologically relevant assessment indices using only a limited number of meteorological and other input data. A comparison between measured and simulated values for global radiation and mean radiant temperature shows that the simulated data closely resemble measured data.


RayMan model Radiation flux densities Mean radiant temperature Human-biometeorological indices Human thermal comfort 



Thanks a million to RayMan users for their suggestions and validations. Both represent the basis for further development of the model.


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Copyright information

© ISB 2009

Authors and Affiliations

  1. 1.Meteorological InstituteAlbert-Ludwigs-University of FreiburgFreiburgGermany

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