The calculated ground temperature exceeds -100 C

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Hi All:

I am trying to run the residential prototype downloaded from the EnergyPlus
website with the TMY3 weather data. But there was a fatal error that caused
termination of the simulation. The prototype file is
"SF_Arizona_Winslow.Muni.AP.723740_elecres_slab_IECC_2012.idf" (I converted
it from version 5 to version 7.2, so that I can run it with Energyplus 7.2),
and the weather file is "USA_AZ_Show.Low.Muni.AP.723747_TMY3.epw".

I have attached both file in the email, in case anyone want to reproduce the
error message.

Here is the error message:

Program Version,EnergyPlus-Windows-OMP-64 7.2.0.006, YMD=2015.02.03
14:07,IDD_Version 7.2.0.006

** Warning ** Output:PreprocessorMessage="GroundTempCalc - Slab" has the
following Warning condition:

** ~~~ ** Slab thickness [0.100 m] reset to 0.122 m for
computational stability.

** Severe ** Output:PreprocessorMessage="GroundTempCalc - Slab" has the
following Severe condition:

** ~~~ ** The calculated ground temperature exceeds -100 C [-389.47
C]

** Severe ** Output:PreprocessorMessage="GroundTempCalc - Slab" has the
following Fatal condition:

** ~~~ ** Program terminates due to preceding condition.

** Fatal ** Preprocessor condition(s) cause termination.

...Summary of Errors that led to program termination:

..... Reference severe error count=2

..... Last severe error=Output:PreprocessorMessage="GroundTempCalc -
Slab" has the following Fatal condition:

************* Warning: Node connection errors not checked - most system
input has not been read (see previous warning).

************* Fatal error -- final processing. Program exited before
simulations began. See previous error messages.

************* EnergyPlus Warmup Error Summary. During Warmup: 0 Warning;
0 Severe Errors.

************* EnergyPlus Sizing Error Summary. During Sizing: 0 Warning;
0 Severe Errors.

************* EnergyPlus Terminated--Fatal Error Detected. 1 Warning; 2
Severe Errors; Elapsed Time=00hr 00min 0.67sec

I think the major problem is that "The calculated ground temperature exceeds
-100 C [-389.47 C]". I don't know why this will happen. I didn't modify the
prototype and weather file, except the conversion of idf version.

Thanks very much for any suggestion.

Sincerely,

Jianhua

Jianhua Huang's picture
Offline
Joined: 2013-02-14
Reputation: 0

The EnergyPlus Slab preprocessor fails with some weather files when
Evapotranspiration= TRUE. A fix was made to get around this in v8.1.
With v7.2, if you change Evapotranspiration to FALSE, it should run
successfully. EnergyPlus is now at v8.2.
Mike

Michael J. Witte's picture
Joined: 2011-10-01
Reputation: 0

Hi Mike:

Thanks for the information. I just checked the idf file, and it looks that
the evapotranspiration is set to FALSE by default. (I found two
evapotranspiration parameters in the file, and they are both set to FALSE)

GroundHeatTransfer:Slab:BoundConds,
FALSE, !- EVTR: Is surface evapotranspiration modeled
TRUE, !- FIXBC: is the lower boundary at a fixed
temperature
10, !- TDEEPin {C}
FALSE; !- USRHflag: Is the ground surface h specified
by the user?

GroundHeatTransfer:Basement:SurfaceProps,
0.16, !- ALBEDO: Surface albedo for No snow
conditions
0.4, !- ALBEDO: Surface albedo for snow conditions
0.94, !- EPSLN: Surface emissivity No Snow
0.86, !- EPSLN: Surface emissivity with Snow
6, !- VEGHT: Surface roughness No snow conditions
{cm}
0.25, !- VEGHT: Surface roughness Snow conditions
{cm}
False; !- PET: Flag, Potential evapotranspiration on?

I also tried to update the EnergyPlus to V8.1 and V8.2. Unfortunately, none
of them work, and I still get the same errors.

Any other idea what happened? Thanks for any suggestion!

Sincerely,

Jianhua

Jianhua Huang's picture
Offline
Joined: 2013-02-14
Reputation: 0