Thank you for the quick fix @chris . I was wondering what kind of sky the Imageless recipe uses, and if there is way to manually change different skies?
I wanted to run a calculation using the worst case scenario for glare, in my opinion, always sunny with sun
Hi Hristo.
The imageless glare recipe calculates annual glare. Hence it uses an annual weather file rather than using a fixed sky. So you cannot choose a sky type like you would normally do for point-in-time radiance studies.
Hey @Hristo ,
@MarkLabrosse has the right answer here. The recipe uses an annual Wea instead of a point-in-time sky but, if you are interested in studying the worst possible scenario with the Imageless Annual Glare recipe, you can create a Wea composed entirely of clear sky conditions using either the HB Wea from Clear Sky component or the HB Wea from Tau Clear Sky component.
Both of these components use methods for representing clear sky conditions from relatively few input parameters. The Tau Clear Sky model is a little more accurate than the basic Clear Sky model. However, the Tau model requires you to have a .stat file with some aerosol optical data and not all .stat files have these. The basic Clear Sky model only requires Location (lat/lon) info.
Hello Chris,
thank you so much for the response! I was just looking into ways to manipulate the .epw file manually when I saw your post. I will definitely try both Sky models.
Hello @mikkel ,
if I understand things correctly, then the colors here are not matching the result. Blue should mean less glare, but I think in this case it is the opposite.
I have downloaded the recipe from Hydra. Where should I look for mistakes?
Thank you very much,
Hristo
The visualization looks correct to me. If you donât like the default colors, then you should customize them with some LB Legend Parameters.
Imageless Annual Glare in LBT 1.5.
Can I know the DGP value of each hour by this method
I used the same method. The DGP value of 8760 hours is not displayed in the Notepad, but only 259 values. Can you share your file? Or you can answer how to check the DGP value of 8760 hours. Thank you
Hi @tangtang,
I have attached the latest sample file. It shows how to use the component HB Annual Results to Data to create a Data Collection, and there is also a plot of the 8760 values. You can get the values by using the component LB Deconstruct Data.
annual_glare.gh (81.8 KB)
OK, thank you. In addition, I have another question. I want to study the calculation of solar glare with Venetian louvers. Can this method be used to calculate glare under different louver angles
Hi @tangtang,
As of right now you have to run the simulation for each louver angle.
In the future I would like to add support for dynamic shades or aperture groups, but for glare this is a little bit more complicated than doing it for illuminance since we canât just sum the contribution of each aperture group like we can do with illuminance. For the calculation in imageless annual glare, we would have to go a step further back by calculating new matrices (adding dctotal and dcdirect for the aperture groups) and then calculate the DGP.
I did some tests with aperture groups a while ago and the results (DGP) looked promising compared to a fully static model, however, due to the slow runtime of dcglare when recording the DGP values the post processing was quite slow once you start to change the dynamic states. This can perhaps be countered by recreating the calculations made by dcglare with NumPy.
Sorry, I donât fully understand what you mean. I have reviewed some relevant documents. When there are Venetian louvers to calculate glare, most people use the diva plug-in. I havenât found this plug-in. I want to know what methods can accurately simulate and calculate the indoor glare with louvers. thank you
You can use the Imageless Annual Glare recipe, or the Point-in-Time View-Based recipe in combination with the Glare Postprocess component.
I had encountered this issue some months months ago and it is great to see it solved!
At the same time I was wondering if it would be possible to also rotate the view directions on the simulation plane, so that a view direction can face the facade or stand at a 90 degree angle to it.
Could a ârotate viewâ be added to âHB Radial Sensor Gridâ component?
A screenshot of the case
Both HB Radial Sensor Grid and HB Radial Grid from Rooms have the input _start_vec_ which sets the start direction, (0, -1, 0) by default, for all view points in the grid. As of right now, if you only want some of the view points to have a different orientation you would have to create a separate grid for those view points.
thank you @mikkel
The âstart vectorsâ solve my question. Sorry for posting, I have not used the components in a few months.
Thanks for the tip! Separating grids between orientations is an option. I will test eventually what will be the difference in results between these alternatives.
Can I simulate DGP for a specific period of time not annual results? can I also generate data for smaller time steps like 5 minutes data?
Iâm aware that I can create a wea file with subhourly data using stochastic model to compute irradiance data with 1-min resolution from hourly data based on the reference below.
But how can I implement it in dcglare or the imageless DGP?
Walkenhorst et al., 2002, âDynamic annual daylight simulations based on one-hour and one-minute means of irradiance dataâ.
https://www.sciencedirect.com/science/article/pii/S0038092X02000191?via%3Dihub
