I’m here to ask you for help on the case study I’m analyzing.
The model itself is quite basic, I have a floor, a ceiling, a generic obstruction in the center of the room, while the walls are totally open; in addition there is a shading system with metal blades.
Question: Is it possible to assess whether the solar radiation incident on these metal elements causes them to overheat and therefore thermal discomfort for the internal occupants?
I’ve seen these other topics and links related to hydra:
but what if the element with respect to which I calculate the radiant asymmetry are external shading?
I attach image and grasshopper file of the attempt I made.
Sol-air temperature might be what you are looking for. It allows you to aproximate the temperature of surfaces exposed to the sun. It´s described more in detail in CIBSE Guide A:
I have the same issue . the simulation with Energy Plus do not take in consideration the thermal effect .it only consider th benefit of shading . I wanted to evaluate the impact of PV Panels On roof .
I have used PV panels from Ladybug as an HB context before running the simulation on energyplus . and the simulation donot consider the overheat caused by PV panels .
I think my problem was more about calculating the MRT and the relative sight coefficients in a “non-manual” way, in any case I thank you for the suggestion which I will definitely give a reading.
Reading your post I came up with an idea and started looking for related topics which consider the context as shadings, I found this which I think is interesting and even if I have not had the opportunity to test.
If it helps, I´ve done a semi automated process in a couple of cases.
Once you have the surface temperatures, you could use Ladybug Legacy to compute view factors and MRT. However, I don´t know how this feeds into the radiant asymetry model downstream.
I had noticed this as well, but I must admit that this is the first time that I try to use it.
I calculated the temperatures of the blinds starting from the incident radiation with “a * Q + (hext + hint) * (T '- Tamb) = 0” and the surface temperatures with the HB model.
The first problem I encountered in this “manual” process is that the view factors of the lamellae are very low and therefore their influence on the MRT is substantially very low (I get a value of about 16 degrees celsius on July 15 in full sun , which is impossible).
The second problem I encountered, but which I have not yet addressed, is the calculation of the radiative exchange coefficients between the various surfaces for determining the operating temperature (which I think can be a good indicator of comfort at least in this first phase).
The fact that there are all these calculation problems led me to think that there could be a component that would allow us to take this into account, automating the process.
Spoiler: I haven’t found a solution yet, but I’m continuing to search.
