Center for the Built Environment
Calculation of the Solar Load onto Occupants in a Room using Bidirectional Scattering Distribution Functions and a View Factor Approach
- Author(s): Jedek, Christoph
- et al.
As environmental simulations in the building industry become more andmore important, a precise calculation of the solar load onto occupantswithin buildings, for an infinite variety of fenestration devices, wouldrepresent a valuable tool for understanding and predicting the functionalityof buildings.
In this thesis, a new tool is created to calculate the direct and diffuse solarradiant gain onto a detailed model of an occupant, as well as on everysimulated surface inboard of the fenestration. The tool takes into accountany possible fenestration properties and geometric room conditions. Torealize it, a new theory was developed for calculating solar load withbidirectional scattering distribution functions (BSDF) and view factors. Thetool uses several pre-existing programs to obtain the necessary inputinformation.
Two simulations for different buildings in the United States of Americaserve as examples of the practical applicability of the tool. The simulationresults demonstrate the effects of external shading devices and glazingproperties on the solar load on an occupant, both overall and for theoccupant’s individual body segments, through different times of day andyear.
These results can be used directly for analysis, or can be used as inputvalues for subsequent thermal comfort calculation. Similarly, the detaileddistribution of transmitted direct and diffuse radiation onto the surfaces ofthe room provide input for detailed simulations of indoor environmentsnear windows.