Hi guys
I was trying using the command prompt to find the Unified Glare Rating, but the command prompt stated that "findglare: picture read error (Kindly see below image)
Could anyone kindly advise on how to solve this problem?
Thanks
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Desktop Radiance Glare Analysis - findglare: picture read error
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Re: Doubt about calculating of the "hourly solar collection"
Hi,
this guide is really helpful!!!!!
I'm following this to try to find my hourly average electricity produced from my solar collector.
I have one more doubt: when I open the script, after the calculation, I have the same value of radiation every hour for each day.
Did i make some mistakes or should I change something?
Thanks in advance for this
Paolo
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Re: Doubt about calculating of the "hourly solar collection"
Hello Paul,
No you did not make any mistake, only pointed out my sloppy script righting skills 
I see now that the previous script was only running the calculations based on average hourly radiation, which is ok, but not as accurate as a true hourly breakdown. So I tweaked the script to use the same command as when using the Solar Exposure calculations under the Analysis Tab. It looks more in line with what you are after, and you can double check that it is correct by running the Resource Consumption > Hourly Solar Collection for a user defined date range.
Here it is revised and also attached.
--[[------------------------------------------------------------------------------------------------
-- This script calculates hourly electrical output generated from the incident radiation on the
-- selected planar object.
-- Olivier A. PENNETIER | March 2016
--]]------------------------------------------------------------------------------------------------
-- GET MODEL"S LATITUDE ----------------------------------------------------------------------------
lat = get("project.latitude")
if lat < 0 then l = 1 else l = -1
end
-- GET SOLAR COLLECTOR EFFICIENCY AND AREA----------------------------------------------------------
Eff = getUserInput("Solar Collector Efficiency [%]:", 10)
area = get("selection.area")
-- PRINT TABLE HEADERS -----------------------------------------------------------------------------
printf("MODEL: %s", get("model.file"));
printf("INCIDENT RADIATION (W/m2)");
printf("COLLECTOR EFFICIENCY: %0.2f", Eff/100);
printf("COLLECTOR AREA (m2): %0.1f", area);
printf("\nDAY\tHOUR\tRADIATION (W/m2)");
-- RESET CUMULATIVE RADIATION ----------------------------------------------------------------------
cumrad = 0.0
-- SET DAY AND TIME --------------------------------------------------------------------------------
for day = 1,31 do
set("juliandate", day)
for hour = 00,23 do
set("model.time", hour)
-- REFRESH SCREEN ----------------------------------------------------------------------------------
if (get("model.display") ~= 1) and (get("view.visible") > 1) then cmd("view.redraw")
end
-- CALCULATE RADIATION ON OBJECT -------------------------------------------------------------------
set("shading.accuracy", 0)
set("shading.angles", 2, 2)
cmd("calc.solar.day")
radiation = get("results.solar.incident",hour)
cumrad = cumrad + radiation
printf("%03d\t%02d\t%6.1f", day, hour, radiation)
end
end
-- CALCULATE COLLECTOR ELECTRICAL OUTPUT -----------------------------------------------------------
printf("\nTOTAL CUMMULATIVE RADIATION (W/m2): %0.2f", cumrad);
PVoutput = cumrad * (Eff/100) * area
printf("\nTOTAL ELECTRICAL OUTPUT RADIATION (Wh): %0.2f", PVoutput);
Cheers,
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Re: Creating prismatic glass in Ecotect
Hello mahnazmaroufi,
I have never worked with prismatic glass, so I wold not know first hand how to deal with it in Radiance, but I believe it is possible, by adding some texture in the radiance file of the material. Obviously, you cannot use the input straight from Ecotect for this, you will have to right this particular material's specific radiance file and then tell Ecotect to look for *.rad file (check that option box at the summary page of the wizard, and make sure to put that *.rad file in the same folder as your*.eco file).
Now, as far as what texture and its parameters to insert in the file, I do not know what it would be, but a good start would be to read up this good paper here: http://arxiv.org/pdf/1307.4214.pdf ; It does talk about how to model prismatic glass using the dielectric material instead of the typical glass material, combined with a texture parameter. You will have to experiment until you achieve the results closest to what is to be expected based on your prismatic glass specific properties.
Cheers,
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Re: Doubt about calculating of the "hourly solar collection"
Thanks a lot for the fast answer. You know it very well!
The only problem now is that if i run a simulation for one month, as example, I have the same results every day in the correct time period. Do you have any suggestion?
Thanks again
Paolo
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Re: Desktop Radiance Glare Analysis - findglare: picture read error
Hello EIM123,
uhmm. I have never used the findglare command, only evalglare.
Do you know if there is some limit on the size of the .pic that can be read by findglare? I know that evalglare can only read up to 800X800 pixels images.
Is your *.pic image located directly under the radiance folder? If not, you have to use the command to access the location of your *.pic file, which is not necessarily your Radiance folder. It looks from your screen shot that your image is directly under your Radiance folder.
Is the .pic image from a illuminance or luminance calculation? Or simply a real life HDR photograph? I do not know if findglare would work if it tries to read an illuminance (lux or fc) image.
Personally, I gave up using these command prompt for glare analyses and now I use a free too called hdrscope which has the evalglare command embedded in a GUI which makes it much faster to use. It will also create a new image identifying the area of high luminance (glare), give glare indices and I think it has more options than findglare; for example you can define a task area to compare the glare to.
Either way, let us know if you are able to make it work using the command.
Cheers,
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Re: Doubt about calculating of the "hourly solar collection"
Hi paul.90,
Uhmm. Not sure what is happening there. Works on my machine 
Try to run a quick Solar Exposure calculation under Analysis > Solar Exposure > Calculate with your object selected. Then re-run the script and see if it works. Also, run the Resource Consumption > Hourly Solar Collection for the same dates and you should get the same result for the total. if that does not work, email me or post your *.eco file here so I can have a look.
Cheers,
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Re: Doubt about calculating of the "hourly solar collection"
Thanks a lot for the advice. All the conversation was really helpful.
BR
Paolo
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Importing from rhino serious problem!
! I followed all the instructions for saving a rhino model.(dxf, all exported as closed meshes) my model is really simple (few closed polysurfaces).
Unfortunately after saving as dxf, Ecotect doesn't let me import it, it just diesn't read the file!
I've tried to re-open the dxf file in rhino and in Autocad and it works perfectly.
I also saved in a older dxf version (2000) but still nothing.
Any suggestions?
I just installed the program and I really want to use it
thanks
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Re: create view point file for Daysim
Dear Pennetier1,
Sorry for bothering you again. I would like to ask your opinion about hrdscople. Specifically I made glare analysis in my room and although some colours appear in the render image, the analysis results are the following:
dgp,dgi,ugr,vcp,cgi,Lveil: -1.#IND00 -1.#IND00 -1.#IND00 -1.#IND00 -1.#IND00 -1.#IND00
What does this mean? Why it cannot end up with numbers?
I attached my render image:
Thank you in advance,
Chryso
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Re: create view point file for Daysim
Hello chrysohe,
I do not know what this mean either.
Can you send me or post your *.pic file you are using? I can try on my end to see what I get.
Thanks,
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Re: Desktop Radiance Glare Analysis - findglare: picture read error
Hi Olivier A. PENNETIER,
Thanks for the help.
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Ecotect and Radiance Daylight Results Discussion
Hi guys,
I have a question. Initially, I have run the daylight analysis in the Ecotect and I was suppose to extract out the lux levels on the different periods. However, in the Ecotect, i believe it is impossible to do run the daylight on different periods. Thus, I exported the daylight results to the Radiance and imported back the Radiance results to Ecotect. Here comes the problem, when I imported back the results to Ecotect, those areas with completely enclosed/no windows (Highlighted in RED), there was some daylight coming in, which does not make sense.
Thus, I would like to find out if there is anything wrong with my model or other problems?
Could anyone kindly advise on how to solve this problem?
Thanks,
YK
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create view point file for Daysim
Hi Pennetier1,
I attached two .pic files. The RCP_C1 works and it can end up with results. The RCP_C2 does not work and it is the one that I am interested about.
I don't understand why this happens.
Thank you in advance,
I am looking forward to hearing from you.
Chryso
I attached two .pic files. The RCP_C1 works and it can end up with results. The RCP_C2 does not work and it is the one that I am interested about.
I don't understand why this happens.
Thank you in advance,
I am looking forward to hearing from you.
Chryso
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Re: Importing from rhino serious problem!
Hello liahb,
I do not use Rhino so it may be difficult for me to help you troubleshoot this issue.
Have you tried other format to import in Ecotect? I personally like the .obj import option better than .dxf.
*.3ds format it also an option but it makes it more difficult to clean up as it imports each object as a layer, or almost.
I have also had quite a bit of luck using Sketchup as an intermediary program to convert format; you just have to keep track of your units...
I am curious, what does the error message says exactly?
Cheers,
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Re: Ecotect and Radiance Daylight Results Discussion
Hello EIM123,
Wow. The Radiance results do not look like anything like the Ecotect results. Not even close, so there is definitively something amiss here, but hard to troubleshoot without the file. If you want to send me your *.eco file or the portion of it causing the issue, I can have a look for obvious things.
Are you using your own custom *.rad material files or have Ecotect do that for you?
Is your analysis grid at task level @30" or so?
My first gut feeling is that something is not right with the modeling of the FLOOR or CEILING object, but I would need to have the file to double check.
Cheers,
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Modelling Thickness of the walls, floors and windows
Hi,
For the solar/daylight analysis, I would like to know if we need to model the thickness of the walls, floors and windows. Does it affect the results? Let’s say the Solar Heat Gain Coefficient and Visible Transmittance of the 6mm single glazed window is 0.94 and 0.737 respectively. Do we need to draw the 6mm or just the single plane will do?
Could anyone kindly advise on how to solve this problem?
Thanks
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Re: Modelling Thickness of the walls, floors and windows
Hello EIM123,
The typical answer is NO. But of course, there are always exceptions...
WINDOW objects should never be modeled with a thickness, because there is certain glazing properties assigned to the single layer object. If you were to "double up" on the layers, it would be the same as having two windows. Just make sure that the transmittance is set to 1.0 while running thermal analyses, with the SHGC set to what the manufacturer's specification: these two options work the same way in that they both decrease the solar radiation, so if setting both of them as per your manufacturer's specifications, you would be reducing the solar gains by too much.
WALLS, FLOORS and CEILING objects typically do not need to show any thickness for most analyses, as the assembly and actual thickness of each object is defined in the Layer tab of the Material Properties window, which Ecotect accounts for; but sometimes, especially for daylighting studies, the thickness of the walls around your glazing will reduce some of the incoming light. This can be easily modeled without "doubling up" the walls by simply creating reveals objects on the outside of your windows:
In that way, the light will be blocked from entering the space the same way it would with the thickness of the walls. IN most cases, it will only reduce the daylighting by a small fraction, so I would first make sure that the daylighting results look correct with a simpler model, then little by little, increase the level of detail for the model, which may impact the overall light levels (reveals, columns, furniture etc...)
For your example, simply assign the Transmittance to your single plane WINDOW object; SHGC is only useful for thermal analyses, so it will not matter for daylighting analyses.
Hope that helps,
Cheers,
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Re: create view point file for Daysim
Hello chrysohe,
uhmm, very strange indeed. The culprit image works just fine on my machine, using hdrscope:
I get a DGP of 0.23, which is a low threshold for glare.
I have opened your *.RIF file in the Radiance Control Panel (Ecotect menu > Tools > Edit radiance Project) and all looks good from there.
Have you tried the same file multiple times? I wonder if your *.PIC did not get corrupted at some point, but then the one you sent me works just fine on my machine, so I suspect an issue with hdrscope... Does it still work for the first *.PIC image?
I would try to uninstall hdrscope and re-install again and see what happens.
Do you know what version of Evalglare you are using? How about Radiance?
Here is a fc shot of your view using another tool called FalseColor, which allows to display a logarithmic scale:
If it still does not work, I would email hdrscope to ask about the specific message you received. I have emailed them in the last few month and they were quite responsive and helpful. There is a contact link on their website for bug report. Either way, let me know how it goes.
Cheers,
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Re: Ecotect and Radiance Daylight Results Discussion
Hello EIM123,
I have had a look at your model and in general, it looks fine and I was able to run a acceptable Radiance pass at it; but there were a few items that would require your attentions for better results:
1. Your glazing objects are doubled - we have discussed this in a separate post - so that your VT is actually not quite correct. If you want your glazing to be 60% VT and you are modeling two window panes, then you should make each window pane with a VT = 77.45%, so that doubling this would give you a cumulative 60% VT for each assembly. I know it is somewhat painful to have to delete these double window pane as most CAD software will export the entire assembly that includes the two (actually 6) panes. I am working on a scripts that could hopefully allow the user to "clean up" their model and get rid of the extra pane, but not yet there...
2. The issue you were having with some light coming into your space is, I believe, caused by the analysis grid itself. I think some of the nodes are actually on the outside of the building; it is hard to see, but if any nodes can see the outside, then they will pick up these high values. It makes it even more difficult when your model is at an angle, as the analysis grid will not quite match up the building, with "teeth" and edges.
3. Be careful about your material: I see that the ROOF object has a colour of almost 0 - perfectly black. This means it would absorb most of the light, so any bouncing light would be absorbed and this would result in a darker space than actuality. Same thing with your ceilings: they use the same colour (reflectivity) as your floor (40%), which is in line for your floor objects, but quite dark for typical ceilings (usually in the 80-90% range). Your walls have a good 70% reflectivity.
4. What type of file did you use to import the model? There are a lot of 0-area wall objects, which converts into these circular objects in the Visualization window. I have a scripts that helps identify these 0-area objects but there were so many that I need to re-write my script to take care of this (delete them automatically). I think it would simplify the model and make calculations faster.
In general, I would reduce the analysis grid's number of cells for quick analyses, until you feel it is about right, then you can increase the number of cells for final analyses. Your model took me about 40 minutes on a fast computer, and that is too high to trouble shoot any issues.
Lastly, I believe you are missing a window object next to object # 3337, but that is not very important here.
I hope this helps a bit. Try to make sure your analysis grid stays within your spaces to be analyzed - no need to have the grid touching the outside walls. Have a look at this article on the topic.
Cheers,
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