I’m sorry that I’m so late in getting back to this but I finally have the script for you that does the gradual opening with simple ventilation objects. You can find it all in this Grasshopper sample:
Essentially, you set up your Pollination/Honeybee model exactly as you did before by assigning an operable area fraction to your windows for the maximum amount and setting the controls for 26C:
But this time, you do NOT pass the model through the HB Airflow Network component and instead just write out the OSM. Then, I have a little Python component that will edit the simple ventilation objects in the OpenStudio Model and re-save it:
It also adds a ZoneVentilation:WindandStackOpenArea object at the end for each window that controls the night time opening with a special schedule and the controls I outlined in the previous post.
Let me know if you have any questions, @milog . Hopefully, this gives you everything that you need for the CIBSE TM59 standard now.
Hi @chriswmackey, I’ve been having a look at your logic for gradual openings. Thanks for creating this!
One thing I noticed in the AFN script was that the window opening profiles might not be behaving as expected? It seems like during the UK summer months (the plot below selected for HOYs 5287-5453, so around August time), the windows don’t seem to be opening at night even though the room air temperature exceeds 23 degrees for quite a lot of the hours, which meant my bedrooms were getting fails when tested against the TM59 criteria.
Do you know what might be the reason for this? I set up my script in the way that you described above.
I tested your simple vent script as well and my bedrooms passed the night time criteria with that, but unfortunately I don’t know a way to check the window openings without the AFN component.
Thanks for letting us know but I cannot recreate the situation you see in your graph using the AFN-based sample file that I uploaded above. I looked at the opening factor outputs and it seems pretty clear that the windows at night are being left 100% open or 100% closed based on the 23 C threshold:
The windows only remain open over night if the room air temperature at 11PM is above 23C. So it is not going to get triggered overnight even if the room air temperature climbs above 23C during the night.
