Re: [EnergyPlus_Support] EnergyPlus/COMIS error: MATRIX SINGULAR FOR ZONE #2

["Joe Huang" <yjhuang@xxxxxxx>]

Ming,

I have repeated your steps with the example file and found that this error
(MATRIX SINGULAR FOR ZONE #2) was occuring due to your third change where
you reduced the Air Mass Flow Coefficient from 0.001 to 0.0001.  The problem
is caused by the intermediate COMIS input file (eplusout.cif) not being
written to the sufficient level of precision, so that the input 0.0001
appeared as 0.000, i.e., interpeted as a flow coefficient of 0.  I solved
the problem by increasing the precision for writing the flow coefficient and
exponents from three decimal points (F10.3) to five decimal points (F10.5).
I will upload that fix to the EnergyPlus server on Monday.  Until the
correction makes it into the compiled code on the server, please keep the
flow coefficients and exponent at above 0.001.  Even after the fix is
implemented, you need to keep them at above 0.00001.

Joe
----- Original Message -----
From: "waspoorboy" <mingsbox@xxxxxxxxxxxxxx>
To: <EnergyPlus_Support@xxxxxxxxxxxxxxx>
Sent: Tuesday, December 09, 2003 11:20 AM
Subject: [EnergyPlus_Support] EnergyPlus/COMIS error: MATRIX SINGULAR FOR
ZONE #2


> To reproduce this problem,
> I took example file 3zvent.idf
> #1: Delete all cracks. [only two window and one door left]
> #2: Remove East_Zone from COMIS ZONE DATA
> #3: Change the Air Mass Flow Coeff from 0.001 to 0.0001
> #4: Execute EnergyPlus and Fatal error will be there.
>
> COMIS AIR FLOW:OPENING,
> WiOpen1,  !- Name
> 0.001,  !- Air Mass Flow Coefficient When Window or Door Is Closed
> 0.667,  !- Air Mass Flow Exponent When Window or Door Is Closed
>
> Is this problem solvable ?
> Thanks,
> Ming
>
>
>
> To unsubscribe from this group, send an email to:
> EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx
>
> The primary EnergyPlus web site is found at:
> http://www.energyplus.gov
>
> The group web site is:
> http://groups.yahoo.com/group/EnergyPlus_Support/
>
> Attachments are not allowed -- please post any files to the appropriate
folder in the Files are of the Support Web Site.
>
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>


------------------------ Yahoo! Groups Sponsor ---------------------~-->
Buy Ink Cartridges or Refill Kits for your HP, Epson, Canon or Lexmark
Printer at MyInks.com. Free s/h on orders $50 or more to the US & Canada.
http://www.c1tracking.com/l.asp?cid=5511
http://us.click.yahoo.com/mOAaAA/3exGAA/qnsNAA/dkFolB/TM
---------------------------------------------------------------------~->

To unsubscribe from this group, send an email to:
EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx

The primary EnergyPlus web site is found at:
http://www.energyplus.gov

The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/

Attachments are not allowed -- please post any files to the appropriate folder in the Files are of the Support Web Site.




 

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/