sDA calculation


#1

Hi,

I think that there could be an error in the ouput from the sDA component.
The sDA calculated from the DA results gives me a different result than the one from the sDA component.

Am I doing the right calculations?

Best regards,

Federico


Optimisation with Honeybee + ASE and sDA not avaible anymore
#2

Hi, I am having the same issue. It seems sDA is too low (almost 2 or 3%) for north oriented windows with descent sizes. One thing I notice is that DA is insensitive toward occupancy schedule.

I used the same approach as you illustrated in the image to calculate sDA but when I disconnect the schedule, the calculated sDA did not change! So my interpretation was that probably DA is insensitive toward the schedule. But UDI got updated.


#3

Hi @saram,

Sometime you need to disable and enable again the component, but I do not think that this is the case.
I checked the DA and sDA output for the same simulation but with different schedules, and I can see the changes.
Maybe the problem is with the schedule component. Check the values with ladybug 3D chart component.


#4

@Federico587,

Thank you for double checking the results and reporting this. This looks like a bug. I checked the source code and it seems I have calculated the % of time instead of the % of area for sDA.

This is a major bug and I’ll try to fix it as soon as I can. We should have a new release soon to address this issue.


#5

Hi @mostapha,

it is a pleasure that I can contribute just a little to this fantastic tool!
If I may, since we are talking about bugs, do you mind have a look to the schedule component?
As it is discussed her with @saram, it seems like the this component behavior is a little strange.

It is fantastic that you always improve this tool. Thanks.
Best regards,

Federico


#6

4 posts were split to a new topic: Blinds/shades operation in sDA calculation


#10

The original bug in sDA calculation is now fixed. I can’t recreate the issues with the schedule myself. @saram has provided me an example which will hopefully recreates the error. I will discuss the blind state discussion in a separate reply.


#11

@saram, I think in you case the DA values didn’t go lower than 50 so it didn’t change the sDA. From the cases that I have tested the values are changing after changing the schedule.


#12

Thanks for fixing it. Please let us know when you are applying the shading algorithm to LEED sDA calculation.


#13

Hi @saram, You should follow this topic for blinds operation implementation and share your thoughts: Blinds/shades operation in sDA calculation