
MODELING NOTES FOR ASHRAE STANDARD 140-2007 - EXAMPLES

===============================================================================
OVERVIEW
===============================================================================
This document contains examples of modeling notes entered in the 
S140outNotes_Sec5-x.TXT file.  Examples are provided to guide in filling out 
the S140outNotes_Sec5-x.TXT file.

Note that in this file sample notes refer to different sections of Standard 
140-2007.  In an actual S140outNotes_Sec5-x.TXT file the notes would only 
address one set of tests within Standard 140 (e.g., Section 5.2).


===============================================================================
INTRODUCTION
===============================================================================
This document contains supplemental information about the ASHRAE Standard 
140-2007 tests performed.  One S140outNotes document is provided for each 
set of tests (e.g. one for the building thermal and fabric load tests of 
Section 5.2, one for the space cooling equipment analytical verification tests
of Sections 5.3.1 and 5.3.2, etc.)  Six types of information are provided in 
this document, each in a separate section:

A. Software Information
B. Alternative Modeling Methods
C. Equivalent Modeling Methods
D. Omitted Test Cases and Results
E. Changes Made to Source Code for the Purpose of Running the Tests, where
   Such Changes are not Available in Publicly Released Versions of the Software
F. Anomalous Results

Text at the start of each section describes the content of the section for the
reader and provides instructions to the vendor for supplying the content.  
Sample notes are provided in a separate document (S140outNotes_Examples.TXT).

Notes in this document are limited to the six topics shown above.  Notes must 
be factual and objective and may only refer to the software being tested.  
Notes may not refer to any other software program.


===============================================================================
A. SOFTWARE INFORMATION
===============================================================================
CONTENT: This section contains reference information for the software - the 
vendor, name and version of the software plus operating system and computer
hardware requirements.

INSTRUCTIONS: Supply information for items 1 through 7 below.  Item 8 is
optional and can be used to supply additional, relevant information.


1. SOFTWARE VENDOR:   Dummy Software Solutions

2. SOFTWARE NAME:     Building Energy Simulation

3. SOFTWARE VERSION (unique software version identifier):  1.00.039

4. OPERATING SYSTEM REQUIREMENTS:
                      Windows 98,
                      Windows NT (Service Pack 4 or later),
                      Windows 2000 (Service Pack 2 or later), or
                      Windows XP (Service Pack 2 or later)

5. APPROX HARD DISK SPACE REQUIRED FOR INSTALLATION:
                      Maximum = 45 MB
                      Typical = 15 to 17 MB

6. MINIMUM RAM REQUIRED FOR SOFTWARE OPERATION:
                      128 MB

7. MINIMUM DISPLAY MONITOR REQUIREMENTS:
                      VGA with 600x800 resolution and 256 colors

8. OTHER HARDWARE OR SOFTWARE-RELATED REQUIREMENTS:
                      (none)



===============================================================================
B. REPORT BLOCK FOR ALTERNATIVE MODELING METHODS
===============================================================================
CONTENT: This section describes modeling methods used for tests if the 
software provides alternative modeling methods or algorithms that could be used
to perform the test.

INSTRUCTIONS:  If applicable, provide a separate note below 
for each alternative modeling method or algorithm situation.  Use the 
standard format shown below and supply a separate number and title for each
note.  If not applicable, specify "NONE" in place of the information below.


NOTE 1 - Convective Heat Transfer and Radiative Exchange Related to Both 
         Interior and Exterior Surfaces
         (Section 5-2)
---------------------------------------------------------
1.1 Describe the Effect Being Simulated: 
    Convective heat transfer and radiative exchange related to both interior
    and exterior surfaces.

1.2 Optional Settings or Modeling Capabilities:

1.2.1 HEAT BALANCE = 0;
    Physical Meaning: Interior surface heat transfer calculated using ASHRAE 
    values for combined convective and radiative coefficient with the radiation 
    component subtracted out; interior radiative exchange is determined using
    the balanced mean radiant temperature method. Exterior surface heat 
    transfer calculated using combined coefficients for convective and 
    radiative exchange.

1.2.2 HEAT BALANCE = 1;
    Physical Meaning: Same as Heat Balance = 0, except interior surface 
    convection is calculated based on zone air and interior surface temperature 
    difference.

1.2.3 HEAT BALANCE = 2
    Physical Meaning: Same as Heat Balance = 1, except exterior surface heat 
    transfer is calculated using separate heat transfer coefficients for 
    radiative exchange to sky and ground and for convection to ambient air. 

1.3 Setting or Capability Used:
    HEAT BALANCE = 2


NOTE 2 - Interior Transmitted Solar Radiation Distribution
         (Section 5-2)
-------------------------------------------------------------------------------
2.1 Describe the Effect Being Simulated:
    Interior transmitted solar radiation distribution.

2.2 Optional Settings or Modeling Capabilities:

2.2.1 SOLAR DISTRIBUTION = 0
    All radiation initially hits the floor. Radiation not initially absorbed by 
    the floor is diffusely reflected and absorbed by all surfaces in proportion
    to their area-absorptance products.

2.2.2 SOLAR DISTRIBUTION = 1
    Beam radiation falling on each surface is calculated by ray tracing.  Beam
    radiation not initially absorbed is diffusely reflected and absorbed by all
    surfaces in proportion to their area-absorptance products.

2.3 Setting or Capability Used:
    SOLAR DISTRIBUTION = 1


NOTE 3 - Thermal Behavior of Windows
         (Section 5-2)
--------------------------------------------------------------------------------
3.1 Describe the Effect Being Simulated:
    Thermal behavior of windows.

3.2 Optional Settings or Modeling Capabilities:

3.2.1 "Shading Coefficient"
    Applies the ASHRAE shading coefficient technique to calculate solar heat 
    gain (e.g., see 1989 ASHRAE Handbook of Fundamentals, Chp. 27).

3.2.2 GLASS-TYPE-CODE =< 11
    Applies pre-calculated transmittance and absorptance coefficients based on 
    specified glass-type-code; the coefficients are used to calculate solar 
    gain as a function of incidence angle.

3.2.3 GLASS-TYPE-CODE => 1000
    Window used from the library W4LIB.DAT, where windows are modeled 
    using thermal and optical properties developed with WINDOW 4.0.  [Window 
    4.0 (March 1992) LBL-32091 UC-350, Berkeley, CA, Lawrence Berkeley 
    Laboratory] 

	3.2.3.1 Existing window used from W4LIB.DAT
    	
	3.2.3.2 Custom window developed using Window 4.0 and added to W4LIB.DAT
    
3.3 Setting or Capability Used:
    Custom window developed and added to W4LIB.DAT; see 3.2.3.2 above.



===============================================================================
C. REPORT BLOCK FOR EQUIVALENT MODELING METHODS
===============================================================================
CONTENT: This section describes equivalent modeling methods used to perform
the tests.  When the software cannot model an effect exactly as stated in the
Standard or does not permit the input values required, equivalent modeling 
can be used to perform the test.

INSTRUCTIONS:  If applicable, provide a separate note below 
for each instance of equivalent modeling.  Use the standard format shown
below and supply a separate number and title for each note.
If not applicable, specify "NONE" in place of the information below.


NOTE 1 - Thermal Decoupling of Floor From Ground
         (Section 5-2)
--------------------------------------------------------------------------------
1.1 Describe the Effect Being Simulated:
    Thermal decoupling of floor from ground.

1.2 Section(s) of the Standard where Relevant Inputs are Specified:
    5.2.1.4 and 5.2.1.5.


1.3 Equivalent Input(s) Used:
    Floor modeled as perfectly decoupled from ground.


1.4 Physical, Mathematical or Logical Justification of the Equivalent Input(s) 
    – provide supporting calculations, if relevant:
    
    Logical Justification:  Section 5.2.1.5 states that "...the state-of-the-
    art in ground modeling is not very good even in detailed building energy 
    simulation programs.  To reduce uncertainty regarding testing or other 
    aspects of simulating the building envelope, the floor insulation has been 
    made very thick to effectively decouple the floor thermally from the 
    ground."

    It is clear from this statement the intent is to eliminate floor-to-ground
    heat transfer to reduce the uncertainty in results that it will introduce.
    The prescribed method of doing this is to model a floor with very high
    R-value (R=25.374 sqm-K/W or U=0.039 W/sqm-K).  This assumes that a 
    software program cannot perfectly eliminate floor-to-ground heat transfer 
    and therefore must minimize the error due to floor-to-ground heat transfer 
    via use of a large floor R-Value.    

    The subject program cannot comply with the prescribed floor R-value; 
    however, the subject program can perfectly decouple the floor from the 
    ground.  Because perfect decoupling is interpreted as meeting the intent of 
    section 5.2.1.5, perfect decoupling was used as an equivalent modeling 
    approach.


NOTE 2 - Thermostat Control and Equipment Capacity
         (Section 5-2)
-------------------------------------------------------------------------------
2.1 Describe the Effect Being Simulated:
    Thermostat control and equipment capacity

2.2 Section(s) of the Standard where Relevant Inputs are Specified:
    Sections 5.2.1.13.1 and 5.2.1.13.2

2.3 Equivalent Input(s) Used:
    Heating Setpoint = 20°C, Throttling Range = 0.1°K, Heating Capacity = 
    3.935 kW
    Cooling Setpoint = 27°C, Throttling Range = 0.1°K, Cooling Capacity =
    3.935 kW

2.4 Physical, Mathematical or Logical Justification of the Equivalent Input(s) 
    – provide supporting calculations, if relevant:

    Logical Justification:

    Together sections 5.2.1.13.1 and 5.2.1.13.2 require use of a non-
    proportional thermostat with which the heat extraction rate is effectively 
    infinite when the
    zone air temperature exceeds 27°C and the heat addition rate is effectively 
    infinite when the zone air temperature falls below 20°C.  The intent of 
    these sections is to establish conditions for which equipment cooling or 
    heating output exactly matches the zone load.  This eliminates system 
    effects and system dynamics that could obscure the focus of this test 
    suite, which is zone thermal loads, not system coil loads.

    In the subject software program, use of the prescribed inputs constitutes 
    an unstable control system.  For example, the moment the zone air 
    temperature exceeds 27°C, the system will provide 1000 kW of cooling to the 
    zone.  This quantity of cooling far exceeds the cooling demand, so the zone 
    is overcooled pushing the zone air temperature below 20°C.  The moment that 
    happens the system provides 1000 kW of heating to the zone.  This quantity 
    of heating far exceeds the heating demand, so the zone is overheated, 
    pushing the zone air temperature above 27°C.  A system with this control 
    will rapidly oscillate between cooling and heating.  The system simulation 
    algorithm in the subject program will not be able to converge on a solution 
    state for any hour because of the unstable nature of this control.

    To resolve this problem, a small throttling range was used with the 
    prescribed setpoints, and the cooling and heating capacities were set to 
    values close to the peak cooling and heating demands of the zone.  These 
    inputs were chosen empirically by tuning the inputs until thermostat 
    control instability was eliminated and differences between the system 
    cooling coil load and the zone cooling load and between the system heating 
    coil load and the zone heating load were minimized as much as possible.  
    This approach meets the intent of sections 5.2.1.13.1 and 5.2.1.13.2.

    Note: In the subject program the 3.935 kW capacity is not specified 
    directly.  Instead it is indirectly defined via supply airflow rate and 
    supply temperature.
    The supply airflow was 565.6 L/s, the cooling supply air temperature was 
    20°C and the heating supply air temperature was 27°C.  This yields the 
    capacities as follows.  The 0.994 factor is the standard 1.207 density x 
    heat capacity x correction factor corrected for site altitude.

    Cooling Capacity = 0.994 x 565.6 L/s x (27°C - 20°C) = 3935 W = 3.935 kW
    Heating Capacity = 0.994 x 565.6 L/s x (20°C - 27°C) = 3935 W = 3.935 kW


===============================================================================
D. REPORT BLOCK FOR OMITTED TEST CASES AND RESULTS
===============================================================================
CONTENT: This section describes test cases that were omitted and/or 
individual results of test cases that were omitted along with the reason for
the omission.

INSTRUCTIONS:  If applicable, provide a separate note below to describe
each type of omission.  Use the standard format shown below and 
supply a separate number and title for each note.  If there are no omissions,
specify "NONE" in place of the information below.


NOTE 1 - Light Weight Test Cases
         (Section 5-2)
-------------------------------------------------------------------------------
1.1 List the Case(s) where Results Were Omitted, and which Results Were Omitted
    for the Case(s):

    600   600FF 230   300   420
    610   650FF 240   310   430
    620   195   250   320   440
    630   200   270   395	
    640   210   280   400	
    650   220   290   410	


1.2 Explanation for Omitting the Test Case(s) Results:

    These test cases require modeling lightweight building construction (approx 
    12 lb/sqft floor area).  This is residential weight construction.  The 
    subject software program is intended for modeling commercial buildings 
    and consequently the minimum building construction weight is 30 lb/sqft 
    floor area.  Since the required building construction weight for these 
    test cases  is well outside the range of intended program operation, 
    these test cases cannot be performed.


NOTE 2 - Case 960- Sunspace, All Results
         (Section 5-2)
-------------------------------------------------------------------------------
2.1 List the Case(s) where Results Were Omitted, and which Results Were Omitted
    for the Case(s):

    Case 960 - Sunspace, all results.

2.2 Explanation for Omitting the Test Case(s) Results:

    The required inputs to model this type of configuration are not available
    in this software program.  Case 960 models a passive solar sun room using 
    a thermal storage wall. In order to model this configuration, the 
    associated algorithm would need to compute:

    a. The hourly proportion of solar radiation absorbed by the individual 
       sunlit surfaces within the sunlit portion of the thermal storage wall.
    b. The effect of introducing infiltration in the thermal storage wall 
       section.
    c. Adjacent space heat transfer between the thermal storage wall and the
       interior room.



===============================================================================
E. REPORT BLOCK FOR CHANGES TO SOURCE CODE FOR THE PURPOSE OF RUNNING THE 
   TESTS, WHERE SUCH CHANGES ARE NOT AVAILABLE IN PUBLICLY RELEASED VERSIONS OF 
   THE SOFTWARE.
===============================================================================
CONTENT: This section describes changes to software source code made to allow
the software to run a test, where such changes are not available in a publicly
released version of the software.  In special situations a change to 
source code is necessary to activate a feature or permit inputs needed for
a test, but these features are not available in the publicly released version
of the software.

INSTRUCTIONS:  If applicable, provide separate notes below to
describe each source code modification.  Use the standard format
shown below and supply a separate number and title for each note.
If not applicable, specify "NONE" in place of the information below.


NOTE 1 - Modification of Scheduling Capabilities
         (Sections 5.3.3, 5.3.4)
-------------------------------------------------------------------------------
1.1 List the Change(s) to the source code:

    Include capability for hourly varying schedules, where such schedules may 
    be varied for any day of the year, for sensible and latent internal gains, 
    infiltration, outside air and zone thermostat.  Currently for the subject 
    software’s publicly released version such hourly schedules may only be 
    varied monthly, beginning on the first day of each month and 
    continuing through the entire month.

1.2 List the Test Case(s) Relevant to the Change(s) in the Source Code:

    More flexible schedules are needed as follows:

    * Internal Gains: All cases of Sections 5.3.3 and 5.3.4
      (i.e., Cases CE300 through CE545).
    * Infiltration and/or Outside Air: Cases CE320, CE330, and CE340 only.
    * Thermostat: Case CE350 only.


1.3 Explanation of Why the Change Is Not Included in the Publicly Released 
    Version of the Software:

    Users of the subject software appear to be satisfied with hourly schedules 
    limited to monthly variation.  Changing the source code to accommodate 
    the test cases of Sections 5.3.3 and 5.3.4 for the purpose of testing the
    calculation engine is justifiable. However, without known demand from 
    users for additional scheduling flexibility, it is difficult to justify 
    additional costs related to enhancing the user interface and 
    revising software documentation.



===============================================================================
F. REPORT BLOCK FOR ANOMALOUS RESULTS
===============================================================================
CONTENT: This section provides an opportunity to describe anomalous test 
results.  Describing anomalous results is optional.

INSTRUCTIONS:  If applicable, describe each type of anomalous result in a 
separate note.  Use the standard format shown below and supply a
separate number and title for each note item.
If not applicable, specify "NONE" in place of the information below.

  
NOTE 1 - Zone Air Temperature Variations in Test Cases HE210, HE220, HE230
         (Section 5.4)
-------------------------------------------------------------------------------
1.1 Test Case(s) and Specific Results from the Case(s) which are Anomalous:

    Large differences in minimum/maximum zone air temperatures for test cases
    HE210, HE220 and HE230 versus reference results.

1.2 Explanation of Reason for the Anomalous Results:

    The default settings in the subject simulation program use a 50%/50% mix of
    explicit and implicit solution schemes for solving for the unknown zone
    air temperature of the next time step.

    The explicit solution of a building simulation case tends to become 
    unstable if the conduction through the walls is relatively large
    compared to the thermal storage capacity of the zone.  For simulated
    houses with little or no thermal mass, solving the energy balance to obtain
    the required furnace output may therefore result in oscillating solutions
    when the default simulation settings are used.

    The implicit solution however is stable and its zone air temperatures
    perfectly follow the thermostat settings.

    When a 50%/50% mix of explicit and implicit solutions is used, the zone
    air temperature is sometimes too high and sometimes too low due to the 
    effect of the explicit solution.

    If the fully implicit solution scheme is used, the total furnace loads will 
    only differ slightly from furnace loads predicted using the default 50%/50% 
    mix of explicit and implicit solutions.  Because HE210, HE220 and HE230 
    focus on total furnace load rather than on calculated zone temperatures, it 
    was felt the results using default simulation settings are valid in spite 
    of the anomaly in zone air temperature results.


===============================================================================
<END OF DOCUMENT>
===============================================================================
