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doe21e geometric input

asked 2016-09-29 00:25:38 -0500

ngkhanh gravatar image

I need to input a polygon layout in doe21e. But in manual, the only selection is Box Shape. I tried to use Equest style

"Floor Polygon" = POLYGON         
   V1               = ( 0, 0 )
   V2               = ( 334, 0 )
   V3               = ( 334, 203 )
   V4               = ( 0, 203 )
   ..

but it seems doe21e doesn't recognize that way. Have any way to input space different than rectangular in doe21.e ?

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answered 2016-10-02 23:10:34 -0500

Nick Caton gravatar image

Searching the reference manual for 2.1 I don't believe SHAPE = POLYGON is an option.

Here is the entry for the SPACE keyword SHAPE in 2.1e:

SHAPE - is an alternative method for defining a space. It is simpler than using the space coordinate system. At present there is only one shape -- BOX. This box is defined by the HEIGHT, WIDTH, and DEPTH keywords and the faces of the box are defined internally. The faces can then be referred to by instructions that define their nature (i .. e. EXTERIOR-WALL). Fig. 111.6 shows how a BOX and its faces are defined with respect to the space coordinate system.

In the 2.2 reference manual Vol-1 "Basics", I found the following quote, suggesting POLYGON space geometry definitions were a "new" thing as of 2.2:

There are very few changes in the LOADS input from previous program versions, except for the FLOOR command, the specification of lighting systems, and the specification of shapes for floors, spaces, and walls using polygons.

(emphases mine)

I think you have 2 options:

  1. In 2.1e, a SPACE can specify SHAPE = BOX, then the associated HEIGHT, WIDTH, DEPTH. This permits its child surfaces to simply specify LOCATION (LEFT/RIGHT/FRONT/BACK/TOP/BOTTOM).

  2. It's my impression that your only alternative is to NOT use the SHAPE keyword at all, thus requiring AREA/VOLUME to be specified for each space in lieu of HEIGHT/WIDTH/DEPTH, and requiring each child surface to specify X/Y/Z/AZIMUTH/HEIGHT/WIDTH in lieu of LOCATION.

A qualifier: 2.1e is mostly before my time - I only really got started in the simulation world with 2.2. Others better qualified to answer might be more easily reached by cross posting into the [eQUEST-users] mailing list at onebuilding.org, but if you should need help identifying someone for a cold call let me know and I'll help point you in the right direction!

Thinking forward: If you don't want to script out the math to determine each floor polygon's area - it sounds as though you might have a doe 2.2/2.3 project handy which you could open up in eQUEST, navigate to Building Shell -> Spreadsheet view for spaces, then sort the spreadsheet view by Polygon Assignment. Area for each polygon used for SPACE shapes appears 2 columns to the right.

If you are additionally using polygons in lieu of simpler methods to specify building shades, PV Arrays, or specially shaped interior/exterior/underground surfaces (hard to do these by accident if you are used to leveraging the wizards), you'd need to seek those out separately, but in a similar fashion using the spreadsheet views.

I hope this helps - best regards!

~Nick

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Hi @Nick Caton Actually, i want to convert building shape from OS to doe 2.1e for my assignment. The problem is they should be shown in drawBDL free version (come before polygon is applied). doe2.1e can use polygon for exterior floor and roof but free drawBDL doesn't show polygon and i think about split polygon to rectangular. i meet the problems with coordination system in doe2 . Please help me if you know there is any sources or people dealt with it before. Thanks

ngkhanh gravatar image ngkhanh  ( 2016-10-06 11:35:46 -0500 )edit

I've had limited success converting from e+ --> doe2.2 using SIMEB. The resulting *.inp file includes SPACEs defined with unique polygons, but the child walls are defined via X/Y/Z/HEIGHT/WIDTH/AZIMUTH (independent of the polygons).

Based on what you've shared (again I don't consider myself a doe2.1e expert), it sounds as though SIMEB will get you in the right ballpark.

I should also advise planning for output QC time to fix issues with conversion via SIMEB. I recall issues like missing roofs and interior floors on floors abovegrade being incorrectly converted to exterior floors.

Nick Caton gravatar image Nick Caton  ( 2016-10-06 13:32:45 -0500 )edit

Also: for drawBDL specific questions, @Joe Huang would be a naturally good bet to feel out limitations (and bonus for your query: IIRC he actually prefers doe2.1e as his engine of choice). I think however his contact info on http://www.drawbdl.com/ may be out of date. Here's what appears in his recent email signatures on the onebuilding.org mailing lists:

Joe Huang

White Box Technologies, Inc.

346 Rheem Blvd., Suite 205A

Moraga CA 94556

yjhuang@whiteboxtechnologies.com

http://weather.whiteboxtechnologies.com for simulation-ready weather data

(o) (925)388-0265

(c) (510)928-2683

Nick Caton gravatar image Nick Caton  ( 2016-10-06 13:37:45 -0500 )edit

Thank @Nick Caton i tried SIMEB but it doesn't import .idf made by OS properly (get fault) while the standard geometric library is not stratified my case. I am not sure but might be impolite when ask @Joe Huang about how to get key features in his commercial software drawBDL although i just try to avoid boring repeated input step for my school assignment. Most of doe2.1e input is ok except geometry :(.

ngkhanh gravatar image ngkhanh  ( 2016-10-06 21:30:02 -0500 )edit

I can't constructively comment regarding drawBDL problems or OS export issues as these are not tools I've used much. Perhaps you could dig into & edit the OS-generated IDF file to resolve the error/fault you're observing in SIMEB... Maybe a new question (with pertinent details) is in order to re-address/summarize this query as an OS exporting / SIMEB importing issue?

Nick Caton gravatar image Nick Caton  ( 2016-10-10 13:42:22 -0500 )edit

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Asked: 2016-09-29 00:25:38 -0500

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Last updated: Oct 02 '16