Confusion on solar radiation on facades simulated using Daysim

asked 2023-04-14 01:31:27 -0500

kim's avatar

updated 2023-04-14 12:35:55 -0500

Hello friends:

I am writing to seek your assistance regarding a simulation issue we encountered while using Daysim. We have been using Daysim to simulate solar irradiation on building surfaces for a small case study in Singapore based on a weather file collected from the local climate station. However, we found that the simulation results for facades are confusing.

Specifically, we have generated figures for each month, at a fixed time, to show how the facades’ irradiation changes based on global horizontal irradiation (GHI). For a given month and time of day, there is little difference in the angle between sun and buildings, so we would expect the larger the GHI, the larger solar irradiation. However, we have found that for facades, the curve initially increases and then decreases, particularly at times of day when there is no direct irradiation on facades, such as the East facades in the afternoon and West facades in the morning. (See the attached link above) This occurs for all facades and buildings we have simulated in Singapore.

We are writing to inquire about the cause of this phenomenon and how it works in Daysim. We would greatly appreciate it if you could provide us with any insights or explanations regarding this issue.

Thank you very much for your assistance!

edit retag flag offensive close merge delete


@kim I noticed that you deleted your original post on this topic. In the future, you can edit your post to add/change details -- you don't have to delete posts and create entirely new ones.

Aaron Boranian's avatar Aaron Boranian  ( 2023-04-14 12:32:45 -0500 )edit

Thank you for letting me know, as I wanna upload a figure but failed.

kim's avatar kim  ( 2023-04-14 20:41:17 -0500 )edit

@kim ah, that's because you don't have enough karma points yet to upload an image. Again, you could have edited your original post to provide the GitHub link that you shared to the image. Either way, no harm done.

Aaron Boranian's avatar Aaron Boranian  ( 2023-04-16 19:07:59 -0500 )edit