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How do I manipulate WWR in eQUEST detailed mode?

asked 2014-10-09 08:04:18 -0600

yongqingzhao's avatar

updated 2015-11-13 17:58:58 -0600

When we perform energy analysis in preliminary design stage ,there is a situation often occurs,which is the Window to Wall Ratio (WWR) is frequently changed. But in eQUEST, WWR can only be set in wizard mode.And once we enter the detailed mode,we can not return wizard mode.So if we have entered the detailed mode,how can we change the WWR? Is there a way to manipulate WWR in detailed mode?

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How do I set WWR in eQuest detailed mode? I'll take "eQuest hacks" for $400, Alex.

__AmirRoth__'s avatar __AmirRoth__  ( 2014-10-09 08:30:09 -0600 )edit

Can't you understand the method above,or didn't I make it clear?

yongqingzhao's avatar yongqingzhao  ( 2014-10-09 08:40:16 -0600 )edit
1

Answering your own question, tutorial-style, is perfectly acceptable and encouraged (on all Q&A websites), and this specific solution seems worthy.

But you should still make the question clear, and you should use the "Answer your own question" checkbox when submitting the question (or answer it later), so that the question and answer are separate. This will also give the opportunity for other people to share alternative answers.

Please rephrase your question and add the answer in the dedicated section.

Julien Marrec's avatar Julien Marrec  ( 2014-10-09 09:03:59 -0600 )edit

@yongqingzhao. Sorry, I was making a too-obscure US-specific cultural reference. I will try hard to refrain in the future. These kinds of "hacks" (in the good sense) are exactly the kind of thing UnmetHours needs. Just please, as @JulienMarrec explained, phrase your question as a question and paste the workaround as the answer to that question, so that people can find it more easily. Please also retag the question with 'equest' (just mis-spelled is all) and maybe also 'wwr' so that it gets picked up properly in searches. Thanks for this neat contribution!

__AmirRoth__'s avatar __AmirRoth__  ( 2014-10-09 10:05:40 -0600 )edit

3 Answers

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5

answered 2014-10-11 08:56:40 -0600

yongqingzhao's avatar

updated 2014-10-20 00:51:50 -0600

Below It's My solution:

Firstly,set WWR to value as large as possible in wizard mode,and then enter the detailed mode.

Secondly,create four global parameters,named E,S,W and N ,which represent for East,South,West and North WWR respectively.

Thirdly,default the height of all windows using follwing expression.

if (MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360) >= 0

  && MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<60 ) then  

#PA("N")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")  

else if(MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)  >= 300 

    && MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<360 )

    then #PA("N")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")       

        else if(MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)  >= 60

            && MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<150 ) 

            then  #PA("E")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")           

                else if(MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)  >= 150 

                    && MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<210 )  

                    then  #PA("S")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")                

                    else  #PA("W")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")                

                    endif           

                endif       

        endif 

endif

If you want to change WWR,you can only change the global parameters.For example:

In your project,

East WWR is 30 %,

South WWR is 50 %,

West WWR is 20 %,

and North WWR is 40 %.

In eQUEST detailed mode,you can modify global parameter E to 0.3,S to 0.5,W to 0.2 and N to 0.4.

Though above expression can implement the WWR setting,a warning "expression too long" will occur.So I modify the expression to solve it,Which is shown as following:

 if (MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360) >= 0
  && MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<60 ) then  
#PA("N")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")  
else if(MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)  >= 300 
&& MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<360 )
then #PA("N")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")       
else if(MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)  >= 60
&& MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<150 ) 
then  #PA("E")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")           
else if(MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)  >= 150 
&& MOD(#p3("AZIMUTH")+#p2("AZIMUTH")+#p("AZIMUTH"),360)<210 )  
then  #PA("S")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")                
else  #PA("W")*#P3("FLOOR-HEIGHT")*#P("WIDTH")/#L("WIDTH")                
endif           
endif       
endif 
endif
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3

answered 2014-10-21 11:18:23 -0600

Here is an expression example that sets WINDOW:HEIGHT based on the parent keyword EXTERIOR-WALL:DEG-FROM-NORTH and other global parameters. This could just as easily be written using if statements with ranges for the resulting angle.

   HEIGHT           = 
{ switch (#p("DEG-FROM-NORTH"))
       case 315 : (#pa("L6GlzgHt_North")*#pa("ResAWWGlzgMult"))
       case 225 : (#pa("L6GlzgHt_East")*#pa("ResAWWGlzgMult"))
       case 135 : (#pa("L6GlzgHt_South")*#pa("ResAWWGlzgMult"))
       case  45 : (#pa("L6GlzgHt_West")*#pa("ResAWWGlzgMult"))
       default : 0.0
  endswitch

The DEG-FROM-NORTH property is documented in the DOE-2.2 help, and is populated using the #CDN BDL function. Here is the expression for the property located in BDLdft.dat:

DEG-FROM-NORTH                                       
{#CDN(#L("AZIMUTH")+#P("AZIMUTH")+#P2("AZIMUTH")+    
      #G("BUILD-PARAMETERS","AZIMUTH"), #L("TILT"))}

For buildings that will be rotated, the resulting DEG-FROM-NORTH value may need to be adjusted to compensate for the rotation.

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Thanks,this method greatly simplify the expression!!

yongqingzhao's avatar yongqingzhao  ( 2014-10-21 20:17:51 -0600 )edit
1

answered 2014-10-20 16:29:28 -0600

How we do it here is we manipulate the window heights to adjust the WtWr.

We copy the window heights to an excel spreadsheet, determine a sizing factor based on how much more or less we want the windows to be, and then multiply the window heights by the sizing factor. Then we copy the new window heights back into eQuest.

This obviously has limits in that you can't increase the window height beyond the wall. We use this method mostly for reducing WtWr's for code compliance in a reference building.

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Comments

1

I have ever used the method you mentioned.But it is not flexible and time consuming with low efficiency.For the limits you pointed,It can be solved.For example,I can increase the window width to ensure the window height not beyond the wall.I can use expression(#p("WIDTH")-0.001) to default WIDTH of all window and set x value to 0.

yongqingzhao's avatar yongqingzhao  ( 2014-10-20 20:14:45 -0600 )edit

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Asked: 2014-10-09 08:04:18 -0600

Seen: 2,532 times

Last updated: Oct 21 '14