DAYSIM Subprogram: ds_illum

ds_illum reads in direct and diffuse irradiances from the DAYSIM weather file (*.wea) and calculates for each considered time step of the year the luminance distribution of the celestial hemisphere. The program uses the Perez sky model which uses building site, date, time, direct, and diffuse irradiances as input variables. The resulting sky luminous distribution is combined via a linear superposition with the daylight coefficients (*.dc) that have been generated with gen_dc. The resulting illuminance output files (*.ill) contains the illuminances at all sensor position specified with sensor_file for all considered time steps of the year. The number of output file can vary and is specified via the keyword shading. An example output file is provided below.

The program requires the following keywords in the DAYSIM header file:


Example

Sample annual illuminance profile for four sensors:

1 1 0.500  0 0 0 0       #January 1st 0AM to 1AM
1 1 1.500  0 0 0 0
1 1 2.500  0 0 0 0
1 1 3.500  0 0 0 0
1 1 4.500  0 0 0 0
1 1 5.500  0 0 0 0
1 1 6.500  0 0 0 0
1 1 7.500  0 0 0 0
1 1 8.500  6200 1638 2243 3746
1 1 9.500  20006 3190 8536 10546
...

© 2017   Created by Christoph Reinhart.   Powered by

Badges  |  Report an Issue  |  Terms of Service