I'm using the perez sky model (custom sky) to calculate the illuminance ( Grid-based ) in DIVA.
Now I have two questions;
1.How can I input Direct and Diffuse radiation in DIVA?
When I chose "Custom Sky Model (Perez Sky Model) ”, only "Global Horizontal irradiation" window appears.
we don't have the option to input direct radiation and diffuse radiation directly into DIVA?
2. What is the theoretical model to transform "Global Horizontal irradiation" to direct radiation and diffuse radiation ?
I guess DIVA transforms global horizontal irradiation into direct and diffuse radiation.
In DIVA / temp folder, the text file (....._sky.rad_transformed.text) appear and I guess this file show the transformed results.
What is the theoretical model to transform them ? How is it transformed into direct and diffuse radiation ?