[blyatman]

Hi everyone, I'm trying to create a UDF which determines whether a ray intersects a cell. For context, I'm trying to determine whether a cell is directly exposed to solar rays. I.e. given the solar position, the UDF would assign a value of 0 to cells which are shaded, and 1 to cells which are exposed.

I'm aware that Fluent has a solar calculator ray tracer, but this only works for faces, rather than cells. I have tried using the DO solar irradiation model, but after spending hours tweaking various parameters, it was still too diffuse and too unreliable to say whether a cell is "shaded" or not.

My UDF coding skills are fairly beginner level, and I currently have no idea on how to even approach this. I was wondering if anyone could provide some help or point me to resources into how I would go about doing this. Alternatively, if you believe such a task would be far too complex for a beginner like myself, please let me know.