[Equest-users] Unique Design Q's
Saurabh Kumar Srivastava
SASV at cowi.com
Tue Jul 31 23:12:22 PDT 2018
Thanks a ton David!
Best Regards
Saurabh
From: David Griffin II [mailto:DGriffin at archnexus.com]
Sent: Tuesday, July 31, 2018 9:41 PM
To: Saurabh Kumar Srivastava <SASV at cowi.com>; equestuser00 at gmail.com; equest-users at lists.onebuilding.org
Subject: RE: Unique Design Q's
Saurabh,
Thank you for reaching out. Please keep in mind, I do not recommend or encourage eQuest users to go to this amount of detail for models because it takes a lot more time and in some cases does not yield more accurate results. Since you inquired, however, I am inclined to provide you with the information. See my responses in RED below…
[ARCH | NEXUS]<http://www.archnexus.com>
DAVID W. GRIFFIN II
BEMP
ENERGY ANALYST
2505 E Parleys Way
Salt Lake City, UT 84109
Office 801.924.5028
archnexus.com<http://www.archnexus.com>
[Twitter]<https://twitter.com/arch_nexus>[Facebook]<https://www.facebook.com/pages/Architectural-Nexus/179588705397563?ref=ts&fref=ts>[Youtube]<https://www.youtube.com/channel/UCYRPWKF-yp-AUiI8ia2XfKw?feature=mhee>[LinkedIn]<https://www.linkedin.com/company/architectural-nexus>
From: Saurabh Kumar Srivastava [mailto:SASV at cowi.com]
Sent: Monday, July 30, 2018 11:10 PM
To: David Griffin II <DGriffin at archnexus.com<mailto:DGriffin at archnexus.com>>
Subject: Unique Design Q's
Hi David,
It's so kind of you to share, a really nice model of, a project you worked on.
It looks fantastic and intrigues me, how you modelled :
· Parapets
Parapets are created using Building Shades which were recently updated in DOE 2.3 to include polygon based geometry. I set my zoning up in AutoCAD and bring that file into eQuest to make things easier for me. There are several advantages to doing so – including quickly and accurately placing building shades in eQuest. The trick is to locate the eQuest ‘origin’ for the model in your AutoCAD file. Then you can quickly figure out the x, y, and z coordinates needed to place the geometry. However, I would refer you to the Modelling Procedures Quick Reference in the eQuest help section for properly placing building shades based on the geometry’s normal vector.
Please keep in mind, eQuest does not treat these parapets like real world conditions. Parapets are notorious for being exfiltration chimneys and weak links in the building envelope insulation system. To eQuest, building shades are adiabatic surfaces that block the sun – nothing more.
· Partially sloped roof
Sloped roofs can be difficult in eQuest, so make sure it is worth the effort before undertaking this task. Again, the AutoCAD file will come in handy for this process. In the wizard, eQuest generally puts the rotation point of a roof surface at the origin of the thermal zone, so when creating thermal zones you’ll need to keep this in mind; i.e. every zone with a sloped roof will need to have its origin start on the axis of rotation. Once out of the wizard, the following things need to happen:
1) The roof tilt and height need to be adjusted to match the design. The example below illustrates the position of a roof for a plenum.
[cid:image003.png at 01D428B2.D8740980]
2) You’ll need to adjust any exterior walls. You could simply put the average height of the wall into eQuest and your due diligence would be considered complete as an energy modeller, but if you want a more visually accurate model, you’ll need to familiarize yourself with creating polygons in the detailed interface. Utilizing the AutoCad file, you can calculate the four points of the geometry with ease and create the polygon. Don’t forget to create the vertices in a counter clockwise manner or you’ll get an error message. When the polygon is created, you simply have to assign the polygon to the appropriate exterior wall.
[cid:image004.png at 01D428B2.D8740980]
It is important to note, this process has been simplified for explanation purposes. You may find sometimes trial and error are needed to accurately illustrate geometry. Just be patient and diligent. You’ll figure out whatever it is that needs to be done to figure out any errors or seemingly unsurmountable barriers.
· Spaces without ceiling
This part of the model should be in every modeller’s toolbox. For this specific example, you’ll need to keep in mind the 25,000 SF building required 17 shells to allow thw wizard to do the heavy lifting for me; i.e. varying ceiling heights, sloped roof, second floor, breezeway, etc. required many zones. An illustration of what the model looked like out of the wizard can be found below.
[cid:image005.png at 01D428B5.2C5756E0]
Anyway, to not have a ceiling in the space, simply make the ‘Flr-To-Flr’ and ‘Flr-to-Ceil’ heights in the wizard the same as illustrated in the screen shot below. eQuest will create an open-to-structure’ space with no plenum.
[cid:image006.png at 01D428B5.2C5756E0]
· Green Screens
Most energy modellers do not attempt to model the effects of vegetation in their models. It is difficult and locate the information required and, in the end, could have very little effect on the model results. Should you choose to model a green screen, you’ll need the following information:
1) Plant species
2) Growth pattern
3) Deciduous vs. Evergreen
4) % Shade
In some cases, you’ll also want to consider evapotranspiration depending on where your outside air intake is, etc. For this model, it was not considered. Additionally, if your model is being utilized to predict first year operation, you might model only the first year’s growth rather than modelling a mature plant. Anyway, the information above is used to create the schedule (multiplier) for the building shade which adjusts the TRANSMITTANCE of the geometry. Thankfully, we have several landscape architects on staff who supply me with the necessary information to accurately complete this task. Again, utilize the AutoCAD file to quickly place the geometry in the model and remember to consider the normal vector of the plane.
[cid:image007.png at 01D428B6.29FBE540]
I'm asking you because, I might soon have to do a similar task for a Bank HQ Building.
I hope this helps you on your future models!
Would be great to learn from you!
☺
Best Regards
Saurabh
COWI A/S.
From: Equest-users [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of David Griffin II via Equest-users
Sent: Tuesday, July 31, 2018 2:14 AM
To: equest user <equestuser00 at gmail.com<mailto:equestuser00 at gmail.com>>; equest-users at lists.onebuilding.org<mailto:equest-users at lists.onebuilding.org>
Subject: Re: [Equest-users] Zones with different roof height on same floor
Tejas,
Great question! I work for an architecture firm as an energy analyst, and I find my life is a lot easier if I go the extra mile to accurately model the building’s envelope in eQuest despite the extra time and effort with a mild increase in accuracy. I have illustrated one of my recent models below which includes green screens, parapets, a partially sloped roof, and spaces with and without ceilings (a lot of overkill). This process is much more involved than the process your model will take. See my step-by-step instructions below.
[cid:image001.png at 01D428AF.CE4DF3B0]
It appears your model will require at least three (3) shells be created in the Wizard – One for portion of the building.
1) Create first shell with height ‘X’
a. All shells should have the footprint of the entire building.
2) Create second shell with height ‘X+N’
a. All shells should have the footprint of the entire building.
b. On the ‘General Shell Information’ screen (1 of 26), make sure you ‘Specify exact Site Coordinates’ in order for eQuest to appropriately assign geometry and locate the shell accordingly.
3) Create shell with height ‘X’
a. All shells should have the footprint of the entire building.
b. On the ‘General Shell Information’ screen (1 of 26), make sure you ‘Specify exact Site Coordinates’ in order for eQuest to appropriately assign geometry and locate the shell accordingly.
When you are done, you should have something that looks like the following illustration. If you have done it correctly, the wizard should create all your interior and exterior walls appropriately as illustrated by the outlined geometry (Red). Of course, I encourage you to add thermal zones as required to each shell to accurately model the HVAC system and other associated loads.
[cid:image002.png at 01D428AF.CE4DF3B0]
[ARCH | NEXUS]<http://www.archnexus.com/>
DAVID W. GRIFFIN II
BEMP
ENERGY ANALYST
2505 E Parleys Way
Salt Lake City, UT 84109
Office 801.924.5028
archnexus.com<http://www.archnexus.com>
[Twitter]<https://twitter.com/arch_nexus>[Facebook]<https://www.facebook.com/pages/Architectural-Nexus/179588705397563?ref=ts&fref=ts>[Youtube]<https://www.youtube.com/channel/UCYRPWKF-yp-AUiI8ia2XfKw?feature=mhee>[LinkedIn]<https://www.linkedin.com/company/architectural-nexus>
From: equest user [mailto:equestuser00 at gmail.com]
Sent: Monday, July 30, 2018 4:43 AM
To: equest-users at lists.onebuilding.org<mailto:equest-users at lists.onebuilding.org>
Subject: [Equest-users] Zones with different roof height on same floor
Hi all Modelers,
This time I have come across a single floor building which has zones with different height. I have attached a roughly drawn elevation as an example (Which is not needed :/) . Can any1 guide me how to model such case as equest allows you to take same height for single floor.
Thanks,
Tejas
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.png
Type: image/png
Size: 22542 bytes
Desc: image003.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image004.png
Type: image/png
Size: 24456 bytes
Desc: image004.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image005.png
Type: image/png
Size: 94172 bytes
Desc: image005.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment-0002.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image006.png
Type: image/png
Size: 30995 bytes
Desc: image006.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment-0003.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image007.png
Type: image/png
Size: 21257 bytes
Desc: image007.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment-0004.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image008.png
Type: image/png
Size: 70013 bytes
Desc: image008.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment-0005.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image009.png
Type: image/png
Size: 19652 bytes
Desc: image009.png
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20180801/6c7ea4d5/attachment-0006.png>
More information about the Equest-users
mailing list