Dear RayMan-Forum, I'm new to RayMan and want to know, if it is possible to calculate a diurnal cycle of insolation using RayMan. And furthermore I want to know if it is possible to calculate an annual cycle. My idea was something like loading in a Fisheye-Photo (exposed to atmosphere and shadowed), get the sunpath due to Location/& Date-Time and then - by combining this two Information - I should know how long and with which power the Sun reaches my Spot.
while I'm not entirely sure what you mean by "insolation", RayMan of course can calculate both, diurnal cycles and annual cycles (given, you have the required input). Of course, RayMan can consider a fisheye image in the calculations.
What do you want to calculate exactly? Could you provide more detail?
Okay. I guess my description wasn't that good. Maybe it's easier if I give insight to my project-ideas. I want to calculate "meteorological parameters" to predict presence of an insect. I have the theory that incoming sunlight leds to the situation, that my insect of interest disappears. Therefore I want to take an hemispheric fish-eye-foto from the sampling site. With this foto and in combination with RayMan I want to calculate a few things: First of all I want to get the SVF (what I already solved) And then I want to get these infos: a) when does the sunlight reaches the sampling site (diurnal cycle), b) how much short waved insolation (mean W/M^2 a day as anual cycle) reaches my spot.
thanks for the detailed description of your project! I think I get what you intend to do and I think all of this is possible with the RayMan model assuming you have the necessary input data.
In general: For working with Fisheye photographs always make sure the've the right orientation and are not flipped (this can be easily corrected with any image processing software, e.g. GIMP). A flipped images (lots of cameras do this!) will not affect your SVF, but it will definitely affect any radiation calculations.
For a) I think its best to calculate solar diagrams with a sunpath (Output --> Diagram(polar)) or, if you prefer numbers, create a "Datafile" with only "Date" and "Time" columns and enable in the menu "Table" the items "Date", "Time", "Sunrise", "Sunset", "Act. duration of sunshine", as well as "Direct radiation". Now calculate a "Data table".
For b) you would require some actual input. Do the same as for a), but also include either cloud cover or global radiation in your input data file. For the output table, additionally check "Global radiation". Make sure, "Reduction of G presetting by obstacles" is checked in "Input" --> "Additional pre-settings".
Hi Dominik, thanks for your post. Because of other stuff I wasn't able to give a reply. Your instructions helped a lot, but there still is a problem. I'm using RayMan 1.2 and there is no possibility to check something like:
"Reduction of G presetting by obstacles" in "Input" in "Additional pre-settings"
Therefore I can't calculate the exact radiation (there is no object-based reduction of radiation). Is there a newer version of RayMan?
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08.02.2017 18:33
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