[Equest-users] *****SPAM***** Re: Repost - how to simulate a revolving door
zhouzarah
zarahzhou at hotmail.com
Thu Feb 25 18:27:46 PST 2016
Thank you so much, Joe, Nick, Keith, Sharad and Julien!Previously, I modeled this as increased infiltration. But your suggestions give me more hint, I need to modify the model for accuracy.
Best regards,
Zarah
To: equest-users at lists.onebuilding.org
From: yjhuang at whiteboxtechnologies.com
Date: Thu, 25 Feb 2016 16:50:35 -0800
Subject: Re: [Equest-users] *****SPAM***** Re: Repost - how to simulate a revolving door
It seems to me there are two distinctly different sources of
"infiltration" through a revolving door -
(1) leakage through the cracks and imperfect seals
(2) bulk air exchange when the door is used and acts like a piston
bringing in Pi*(r2/4)*ht volume of outdoor air and exhausting the
same of indoor air.
The relative importance of the 2 depends entirely on how much the
revolving door is being used.
It might be interesting to do some back-of-the-envelope calculations
to see.
Joe
Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 205A
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
http://weather.whiteboxtechnologies.com for simulation-ready weather data
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"
On 2/25/2016 2:06 PM, Keith Swartz
wrote:
To
estimate airflow through an opening due to wind, see the
2013 ASHRAE Handbook ¨C Fundamentals, page 16.13, equation
37. For stack effect use equation 38. For no wind and no
stack effect see 2014 ASHRAE Handbook ¨C Refrigeration, page
24.5. The wind and stack effect equations are in cfm while
the one from the refrigeration handbook is heat load, but it
might still be helpful for you.
Remember
that the wind is not always blowing directly toward the
door¡unless the building swings on a big weather vane so
that the door always points into the wind! The weather
file has wind direction in addition to the speed.
Keith
Swartz, PE
|
Senior
Energy Engineer
Seventhwave
608.210.7123
seventhwave.org
From:
Nicholas.Caton at schneider-electric.com
[mailto:Nicholas.Caton at schneider-electric.com]
Sent: Thursday, February 25, 2016 11:18 AM
To: sharadcapricious at gmail.com;
equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] Repost - how to
simulate a revolving door
Apologies
for not contributing sooner(I¡¯ve been in a busy week
myself), but I notice a few critical points may have been
missed in the discussion so far:
¡¤
The
numbers 90.1 cites for window (0.4 cfm/ft2 ) and door (1.0
cfm/ft2) leakage are at NFRC-400 testing conditions (75
pascals). These represent
maximum permissible infiltration in a closed state
with head-on windspeed equivalent to 75 Pa.
¡¤
Open
windows & swinging doors will infiltrate much more than
closed assemblies. The real-world problem of airflow
through free openings is rather complicated depending upon
many variables (including relative temperatures, windspeed
direction vs. orientation, building pressurization, stack
effects, whether and where other nearby openings are
occurring¡).
¡¤
Conservatively
& for a back of envelope / sanity check with free
openings, I might consider CFM = hourly windspeed(fpm) x
free area(ft2) on an hourly basis.
¡¤
Revolving
doors by design are never ¡°open¡± in the above sense ¨C see
this image
from
Wikipedia if that isn¡¯t immediately clear:
So
the whole picture is perhaps a bit more complicated than you
might have initially thought, but I believe you will find
eQuest is generally well-equipped to tackle all of the
above!
¡¤
Your
weather file has windspeed data that can be used each hour
for calculations
¡¤
Looking
to your SPACE inputs for infiltration, you can read up on
the variety of options for how sophisticated you want to
make your simulation. Most options do account for hourly
windspeed. In all cases, you can define an INF-SCHEDULE to
account for behavior like swinging doors & windows
opening.
¡¤
If
this is all flying a little too high in complexity for your
purposes/timeframe, I suggest leveraging the wizards to
observe what infiltration schedules and inputs are generated
using a few dummy ¡®shell¡¯ models. Note ¡°perimeter¡± vs.
¡°core¡± infiltration schedules are commonly generated side by
side and will be named accordingly.
¡¤
I¡¯d
personally prefer leveraging a custom hourly report for this
sort of assessment. Starting variables to spot check my
expectations would include
o
SPACE
infiltration (cfm) as calculated,
o
local
windspeed
o
ZONE
temperature
o
ZONE
tstat setpoint
Other
thoughts:
¡¤
Ultimately
you are going to be making a ¡°Yes/No¡± decision based on how
the temperatures in this space float. Step back before
getting too far into the study and make some decisions
regarding what would be subjectively ¡°acceptable¡± comfort
criteria considering anticipated atrium/staircase usage,
occupancy profile, & expectations specific to your
regional climate/locale.
¡¤
High-level
assessment idea, if you don¡¯t want to assess this ¡°manually¡±
via hourly outputs: You could perhaps most simply create a
pair of zone temp schedules reflective of maximum comfort
thresholds, then leverage simulation unmet hours inform how
often & when you cross those lines.
¡¤
At
only 2 stories effects probably won¡¯t be extreme, but keep
in the back of your mind that eQuest/doe2 assumes ¡°perfect
thermal mixing¡± within a zone hour by hour. If your space
does not have fans or other means of consistent circulation,
there¡¯s potential for buoyancy/stack effects in the real
world to result in different conditions on the 1st
vs. 2nd level.
Probably
more than you¡¯re looking for¡ sorry for the wall of text!
~Nick
---------------------------------------------------------------------------------------------------------------------------------------------
Nick
Caton, P.E.
Senior Energy Engineer
Energy and Sustainability Services
North America Operations
Schneider Electric
D 913.564.6361
M 785.410.3317
E nicholas.caton at schneider-electric.com
F 913.564.6380
15200
Santa Fe Trail Drive
Suite 204
Lenexa, KS 66219
United States
*Please
consider the environment before printing this e-mail
From:
Equest-users [mailto:equest-users-bounces at lists.onebuilding.org]
On Behalf Of Sharad Kumar
Sent: Thursday, February 25, 2016 3:04 AM
To: equest-users
Subject: Re: [Equest-users] Repost - how to
simulate a revolving door
Hi Zarah,
As per
my understanding you need to know the cooling load
requirement of any space for any time.
For this one
can do peak load calculations and try to find out the
cooling load requirement of any space at desired time.
I have also
referred ASHARE 90.1 and have found that the swinging
door has 1 cfm / sq. ft. and windows have 0.40 cfm / sq
.ft as infiltration.
............................................................................................................
eQUEST have
the option to input the required infiltration in
Internal load tab and input it in as cfm /sq. ft for the
space.
The
infiltration being input is the total infiltration in
that space.
You need to
have proper weather file as per location, have some
cooling system as per project and proper infiltration as
input.
Then from the
hourly report being derived from the File< Export
File< Hourly result (CSV) and have the finding in
cooling end-use energy.
This will help
you to find out whether that space at any desired time
needs the cooling or not. Additionally one needs to have
proper schedules.
The better
software to have these kind of analyses is IES-VE but
eQUEST can also help.
The design
time is the cooling load having the most peak value of
cooling energy in Hourly report.If the Cooling
requirement is less than 300 hours over the year then
may be you can ignore installing cooling system.
If it is for
the major part of year then you can choose to have
cooling system. Also have a go on the cooling plant
requirement size.
Hope this can
be helpful.
Thanks,
Sharad. Kumar.
Green Horizon
Consulting LLP.
Gurgaon.
2016-02-24 5:17 GMT+01:00
zhouzarah <zarahzhou at hotmail.com>:
Dear eQuesters,
Sorry for the
repost! I do need your help about this due to time
limit. If any one can give a hint, I really appreciate
that!
My client
requires to do a thermal simulation for a two-story
atrium/staircase to check if the cooling system is
required for it. The atrium has a revolving door, which
revolves once every 30 minutes, and the swing door opens
for 30 minutes every 8 hours for shift change. My
question is how to simulate the revolving door and swing
door in eQuest? I noticed that ASHRAE 90.1-2010
mentioned the infiltration from these two types of doors
is 1.0 cfm/ft2 tested at a pressure of at least 1.57
pounds per square foot (psf), but I do not quite
understand what this means and how to use this number in
my model. If any one has an idea, please give the
comments. Thank you so much!
Best regards,
Zarah
_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing
list send a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG
_______________________________________________
Equest-users mailing list
Equest-users at lists.onebuilding.org
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
______________________________________________________________________
This email has been scanned by the Symantec Email
Security.cloud service.
______________________________________________________________________
_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG
_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160226/1cc4e19f/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ATT00001
Type: image/jpeg
Size: 6979 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160226/1cc4e19f/attachment-0002.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ATT00002
Type: image/gif
Size: 1822 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160226/1cc4e19f/attachment-0002.gif>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ATT00003
Type: image/png
Size: 5423 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20160226/1cc4e19f/attachment-0002.png>
More information about the Equest-users
mailing list