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Re: [EnergyPlus_Support] custom weather data





Judging from the responses you've received so far, I think perhaps they're missing the point of your question.

If I read your question correctly, you want to actually record the variations of temperature, solar, and wind speed at different heights and facades of a tall building, and then use EnergyPlus to study the impacts of those variations on the building's energy use.  This is a germaine topic and there's even an ASHRAE Technical Committee 9.12 on Tall Buildings devoted to this topic.  In January 2015, I chaired an ASHRAE Symposium on "Energy Modeling of Tall and Very-Tall Buildings", where the four presenters all discussed how they dealt with this issue.  TC 9.12 has been circulating a RTAR (ASHRAE-ese for preliminary Work Statement) for more than a year on doing exactly what you're planning, i.e., actually gather climatic (and pollution) data on various heights of a high-rise building, so you might want to get in touch with the TC 9.12 to coordinate efforts (I'll send you more contact information via e-mail).

I'm aware that EnergyPlus uses lapse rate adjustments for temperature and logarithmic wind speed profiles to account for changes in elevation. However, both of these are generalized assumptions and have never been verified for an urban setting.  I have seen anecdotal evidence that air conditions in an urban heat island are more turbulent, so it's an open question how much of these generalized assumptions still hold true. I'm also unaware that EnergyPlus does anything with the solar radiation except a geometric transposition to the vertical facades. Therefore, I support what you're trying to do, because it would begin to shed some light on this topic.

As far as importing different weather conditions for different building heights,  the only way I've seen is to create separate custom weather files for each floor and then do separate EnergyPlus simulations for those floors.  That was how one of the presenters at the Chicago seminar (Craig Burton) did his simulations, except (1) he used IES, and (2) he broke up the building into 5 sections by elevation, (3) his fuve weather files were not made from direct measurements, but used various models to adjust the climatic variables in the airport weather data.

If you're going to do this for every floor and all 4 facades of a 30-story building, that would mean 120 weather files. You should be careful not to let the building itself affect your measurements - this would be a big problem with wind speed and direction!  Also, how are you going to measure the solar radiation, pyranometers are way too expensive, but if you mount a LiCor vertically on the wall, you need to do a lot of calibration to make them even roughly consistent.

I frankly think you're being too ambitious, or underestimating the amount of work involved, particularly on the measurements.  Anyway, I wish you the best of luck.  And I'll send you e-mail with the contact information for TC 9.12.

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 205A
Moraga CA 94556
yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx
http://weather.whiteboxtechnologies.com for simulation-ready weather data
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"
On 9/6/2016 8:17 AM, Linda Lawrie linda@xxxxxxxxxxxxxx [EnergyPlus_Support] wrote:
 

the standard weather program that is installed with EnergyPlus can also produce custom weather data.

At 08:14 AM 9/6/2016, Javed Iqbal eee.javed@xxxxxxxxx [EnergyPlus_Support] wrote:

You can edit weather file using following software.

http://bigladdersoftware.com/projects/elements/

On 06-Sep-2016 7:38 PM, "serter iyigunlu serteri@xxxxxxxxxxx [EnergyPlus_Support]" < EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
 

Hello,


Thank you for your response. How about high rise building? Temperature and wind speed are going to be change with altitude. How can I export these data with measured data?


Thanks


Serter Iyigunlu
Mechanical Engineer



From: EnergyPlus_Support@xxxxxxxxxxxxxxx < EnergyPlus_Support@xxxxxxxxxxxxxxx> on behalf of Jim Dirkes jim@xxxxxxxxxxxxxxxxxxxxxxxxxxx [EnergyPlus_Support] < EnergyPlus_Support@xxxxxxxxxxxxxxx>
Sent: Tuesday, 6 September 2016 11:33 PM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] custom weather data
Â
 

I think you have a misunderstanding of "weather". Weather is not different on each facade. Rather, some variables (e.g., surface temperature, solar gains, ground reflectance, shading) differ due to building shape, exposure to sun or adjacent shading or time of day, but the weather is the same for all.
EnergyPlus accounts for all of these. You can report the differences if you wish to do so and then compare them with measured variables, but the weather file is a constant reference. You can also edit / customize a weather file to reflect local variations from TMY data for variables such as dry bulb and wet bulb temperatures.

On Mon, Sep 5, 2016 at 1:57 AM, serteri@xxxxxxxxxxx [EnergyPlus_Support] < EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
 

Hello,

How am I going to create a weather file that includes all four facades of building weather data and also all level of the building weather data into one weather file? I intend to install four sets of sensors (temperature,humidity and wind speed sensor) on one facade and the sensors will be installed four facades of the building. And also I do not want EnergyPlus to calculate CHTC for internal and external of the building. I would like to use CFD program to calculate and send these values to EnergyPlus because I will assess high-level building (30 levels at least).

I would like to use my weather file into the EnergyPlus.  And also I would like to measure weather data for all levels of the building and use these data in EnergyPlus. I do not know how to do it. Could you please help me about that? How am I going to enter these values in to the weather file or is there any way to do it with Energy+.


Regards,


Thank you





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James V Dirkes II, PE, BEMP, LEED AP
CEO/President
The Building Performance Team Inc.
1631 Acacia Dr, GR, Mi 49504

Direct: 616.450.8653
jim@xxxxxxxxxxxxxxxxxxxxxxxxxxx

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a similar kind of supercession in such things as virtue and wisdom 





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Posted by: Joe Huang <yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx>


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