Â
Wenting,
I believe this known issue related to massless materials is addressed in the following document by Henninger and Witte of GARD Analytics.
http://apps1.eere.energy.gov/buildings/energyplus/pdfs/energyplus_hvac_global_tests.pdf
See pp 19-20.
- StuartÂ
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx]
Sent: Friday, October 17, 2014 1:13 AM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] HVAC BESTTEST [2 Attachments]Â
Â
Linda,
Â
The following is the full error messages. For your reference, I attached the idf file also(original and updated version). Thank you.
Â
Â
Program Version,EnergyPlus-Windows-64 8.1.0.009, YMD=2014.10.17 10:12,IDD_Version 8.1.0.009
  ** Warning ** Timestep: Requested number (1) is less than the suggested minimum of 4.
  **  ~~~  ** Please see entry for Timestep in Input/Output Reference for discussion of considerations.
  ** Warning ** Weather file location will be used rather than entered (IDF) Location object.
  **  ~~~  ** ..Location object=UNKNOWN
  **  ~~~  ** ..Weather File Location=Miami/Int'l Airport FL USA TMY--12839 WMO#=722020
  **  ~~~  ** ..due to location differences, Latitude difference=[2.00E-002] degrees, Longitude difference=[2.00E-002] degrees.
  **  ~~~  ** ..Time Zone difference=[0.0] hour(s), Elevation difference=[100.00] percent, [2.00] meters.
  ** Severe ** This building has no thermal mass which can cause an unstable solution.
  **  ~~~  ** Use Material object for all opaque material definitions except very light insulation layers.
  ** Warning ** The Standard Ratings is calculated for Coil:Cooling:DX:SingleSpeed = ZONE1WINDACDXCOIL but not at the AHRI test condition due to curve out of bound.
  **  ~~~  ** Review the Standard Ratings calculations in the Engineering Reference for this coil type. Also, use Output:Diagnostics, DisplayExtraWarnings for further guidance.
  ************* Testing Individual Branch Integrity
  ************* All Branches passed integrity testing
  ************* Testing Individual Supply Air Path Integrity
  ************* All Supply Air Paths passed integrity testing
  ************* Testing Individual Return Air Path Integrity
  ************* All Return Air Paths passed integrity testing
  ************* No node connection errors were found.
  ************* Beginning Simulation
  ************* Simulation Error Summary *************
  ************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning; 0 Severe Errors.
  ************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning; 0 Severe Errors.
  ************* EnergyPlus Completed Successfully-- 3 Warning; 1 Severe Errors; Elapsed Time=00hr 00min 0.97secÂ
2014-10-17 10:21 GMT+09:00 Linda Lawrie linda@xxxxxxxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx>:
Â
That doesn't look like a severe error -- why not paste in the full .err
file?
On 2014-10-16 19:19, dingwenting@xxxxxxxxx [EnergyPlus_Support] wrote:
> Hi,
>
> I got the CE100.idf from others and it was the old version. I updated
> it to version 8.1 and ran it. but got a severe error.
>
> MATERIAL:Regular-R,
> INSULATION-EXT, ! Material Name
> VerySmooth, ! Roughness
> 50.00 , ! Thermal Resistance {m2-K/W}
> 0.9000 , ! Thermal Absorptance
> 0.1000 , ! Solar Absorptance
> 0.1000 ; ! Visible Absorptance
>
> MATERIAL:Regular-R,
> INSULATION-INT, ! Material Name
> VerySmooth, ! Roughness
> 50.00 , ! Thermal Resistance {m2-K/W}
> 0.9000 , ! Thermal Absorptance
> 0.6000 , ! Solar Absorptance
> 0.6000 ; ! Visible Absorptance
>
> CONSTRUCTION,
> LTWALL, ! Construction Name
> ! Material layer names follow:
> INSULATION-EXT,
> INSULATION-INT;
>
> The error message is
>
> This building has no thermal mass which can cause an unstable
> solution.
> ** ~~~ ** Use Material object for all opaque material definitions
> except very light insulation layers.
>
> In Case E100 the wall construction is conposed of only two insulation
> layers.
>
> Who can give me some advice?
>
> Thank you very much.
>
>
>> Links:
> ------
> [1] http://energyplus.helpserve.com
> [2] http://www.energyplus.gov
> [3] http://groups.yahoo.com/group/EnergyPlus_Support/
> [4]
> https://groups.yahoo.com/neo/groups/EnergyPlus_Support/info;_ylc=X3oDMTJlcjZwNDY5BF9TAzk3MzU5NzE0BGdycElkAzMzODc0ODgEZ3Jwc3BJZAMxNzA1MDA3Mzg5BHNlYwN2dGwEc2xrA3ZnaHAEc3RpbWUDMTQxMzUwODc1NA--
> [5]
> https://groups.yahoo.com/neo/groups/EnergyPlus_Support/members/all;_ylc=X3oDMTJmMGU2NzlqBF9TAzk3MzU5NzE0BGdycElkAzMzODc0ODgEZ3Jwc3BJZAMxNzA1MDA3Mzg5BHNlYwN2dGwEc2xrA3ZtYnJzBHN0aW1lAzE0MTM1MDg3NTQ-
> [6]
> https://groups.yahoo.com/neo;_ylc=X3oDMTJkOXV2bnZ0BF9TAzk3NDc2NTkwBGdycElkAzMzODc0ODgEZ3Jwc3BJZAMxNzA1MDA3Mzg5BHNlYwNmdHIEc2xrA2dmcARzdGltZQMxNDEzNTA4NzU0
> [7] https://info.yahoo.com/privacy/us/yahoo/groups/details.html
> [8] https://info.yahoo.com/legal/us/yahoo/utos/terms/Â
__._,_.___
Posted by: Wenting Ding <dingwenting@xxxxxxxxx>
Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx
The primary EnergyPlus web site is found at:
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