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How to match the result of autosizing with idf inputs

My purpose is to avoid the auto-sizing of a lot of components after an initial simulation of the model. Since I'm working with several large idf files, it would be very nice to have an automatic and dry solution for this issue. So, using eppy and some existing scripts, I wrote these following lines of code that can get the key value of objects and size values to and modify the idf accordingly.

There is one problem. I can't find the appropriate output for this purpose. For example, for the AirTerminal:SingleDuct:VAV:Reheat object only 2 autosized values are specified:

AirTerminal:SingleDuct:VAV:Reheat,
    SPACE5-1 VAV Reheat,     !- Name
    ReheatCoilAvailSched,    !- Availability Schedule Name
    SPACE5-1 Zone Coil Air In Node,  !- Damper Air Outlet Node Name
    SPACE5-1 ATU In Node,    !- Air Inlet Node Name
    autosize,                !- Maximum Air Flow Rate {m3/s}
    Constant,                !- Zone Minimum Air Flow Input Method
    0.3,                     !- Constant Minimum Air Flow Fraction
    ,                        !- Fixed Minimum Air Flow Rate {m3/s}
    ,                        !- Minimum Air Flow Fraction Schedule Name
    Coil:Heating:Water,      !- Reheat Coil Object Type
    SPACE5-1 Zone Coil,      !- Reheat Coil Name
    autosize,                !- Maximum Hot Water or Steam Flow Rate {m3/s}
    0.0,                     !- Minimum Hot Water or Steam Flow Rate {m3/s}
    SPACE5-1 In Node,        !- Air Outlet Node Name
    0.001,                   !- Convergence Tolerance
    NORMAL,                  !- Damper Heating Action
    AUTOCALCULATE,           !- Maximum Flow per Zone Floor Area During Reheat {m3/s-m2}
    AUTOCALCULATE;           !- Maximum Flow Fraction During Reheat

But in the output summary table mentioned object has seven size columns! I'm a little confused about how to extract sizing results for my code.

How to match the result of autosizing with idf inputs

My purpose is to avoid the auto-sizing of a lot of components after an initial simulation of the model. Since I'm working with several large idf files, it would be very nice to have an automatic and dry solution for this issue. So, using eppy and some existing scripts, I wrote these following lines of code that can get the key value of objects and size values to and modify the idf accordingly.

There is one problem. I can't find the appropriate output for this purpose. For example, for the AirTerminal:SingleDuct:VAV:Reheat object only 2 autosized values are specified:

AirTerminal:SingleDuct:VAV:Reheat,
    SPACE5-1 VAV Reheat,     !- Name
    ReheatCoilAvailSched,    !- Availability Schedule Name
    SPACE5-1 Zone Coil Air In Node,  !- Damper Air Outlet Node Name
    SPACE5-1 ATU In Node,    !- Air Inlet Node Name
    autosize,                !- Maximum Air Flow Rate {m3/s}
    Constant,                !- Zone Minimum Air Flow Input Method
    0.3,                     !- Constant Minimum Air Flow Fraction
    ,                        !- Fixed Minimum Air Flow Rate {m3/s}
    ,                        !- Minimum Air Flow Fraction Schedule Name
    Coil:Heating:Water,      !- Reheat Coil Object Type
    SPACE5-1 Zone Coil,      !- Reheat Coil Name
    autosize,                !- Maximum Hot Water or Steam Flow Rate {m3/s}
    0.0,                     !- Minimum Hot Water or Steam Flow Rate {m3/s}
    SPACE5-1 In Node,        !- Air Outlet Node Name
    0.001,                   !- Convergence Tolerance
    NORMAL,                  !- Damper Heating Action
    AUTOCALCULATE,           !- Maximum Flow per Zone Floor Area During Reheat {m3/s-m2}
    AUTOCALCULATE;           !- Maximum Flow Fraction During Reheat

But in the output summary table mentioned object has seven size columns! I'm a little confused about how to extract sizing results for my code.

How to match the result of autosizing with idf inputs

My purpose is to avoid the auto-sizing of a lot of components after an initial simulation of the model. Since I'm working with several large idf files, it would be very nice to have an automatic and dry solution for this issue. So, using eppy and some existing scripts, I wrote these following lines of code that can get the key value of objects and size values to and modify the idf accordingly.

There is one problem. I can't find the appropriate output for this purpose. For example, for the AirTerminal:SingleDuct:VAV:Reheat object only 2 autosized values are specified:

AirTerminal:SingleDuct:VAV:Reheat,
    SPACE5-1 VAV Reheat,     !- Name
    ReheatCoilAvailSched,    !- Availability Schedule Name
    SPACE5-1 Zone Coil Air In Node,  !- Damper Air Outlet Node Name
    SPACE5-1 ATU In Node,    !- Air Inlet Node Name
    autosize,                !- Maximum Air Flow Rate {m3/s}
    Constant,                !- Zone Minimum Air Flow Input Method
    0.3,                     !- Constant Minimum Air Flow Fraction
    ,                        !- Fixed Minimum Air Flow Rate {m3/s}
    ,                        !- Minimum Air Flow Fraction Schedule Name
    Coil:Heating:Water,      !- Reheat Coil Object Type
    SPACE5-1 Zone Coil,      !- Reheat Coil Name
    autosize,                !- Maximum Hot Water or Steam Flow Rate {m3/s}
    0.0,                     !- Minimum Hot Water or Steam Flow Rate {m3/s}
    SPACE5-1 In Node,        !- Air Outlet Node Name
    0.001,                   !- Convergence Tolerance
    NORMAL,                  !- Damper Heating Action
    AUTOCALCULATE,           !- Maximum Flow per Zone Floor Area During Reheat {m3/s-m2}
    AUTOCALCULATE;           !- Maximum Flow Fraction During Reheat

But in the output summary table mentioned object has seven size columns! I'm a little confused about how to extract sizing results for my code. code.

How to match the result of autosizing with idf inputs

My purpose is to avoid the auto-sizing of a lot of components after an initial simulation of the model. Since I'm working with several large idf files, it would be very nice to have an automatic and dry solution for this issue. So, using eppy and some existing scripts, I wrote these following lines of code that can get the key value of objects and size values to and modify the idf accordingly.

EDIT:

There is one problem. I can't find the appropriate output report for this purpose. For example, in the AllSummary table report for the AirTerminal:SingleDuct:VAV:Reheat object only 2 autosized values (maxmumn number of 6 is possible) is specified but following table has 10 columns for each row (object):

image description

Below the tables, energyplus report states that:

User-Specified values were used. Design Size values were used if no User-Specified values were provided. Design Size values may be derived from alternate User-Specified values.

Considering the comment, it can be said that:

  • If you fill autosizable fields with your own calculations, energyplus would report both user-specified and autosized values.
  • If you leave autosizable fields blank, energyplus would report autosized values.
  • Some columns are specified:

    AirTerminal:SingleDuct:VAV:Reheat,
        SPACE5-1 VAV Reheat,     !- Name
        ReheatCoilAvailSched,    !- Availability Schedule Name
        SPACE5-1 Zone Coil Air In Node,  !- Damper Air Outlet Node Name
        SPACE5-1 ATU In Node,    !- Air Inlet Node Name
        autosize,                !- Maximum Air Flow Rate {m3/s}
        Constant,                !- Zone Minimum Air Flow Input Method
        0.3,                     !- Constant Minimum Air Flow Fraction
        ,                        !- Fixed Minimum Air Flow Rate {m3/s}
        ,                        !- Minimum Air Flow Fraction Schedule Name
        Coil:Heating:Water,      !- Reheat Coil Object Type
        SPACE5-1 Zone Coil,      !- Reheat Coil Name
        autosize,                !- used for size calculation and they are user-specified values from other objects. They will be reported as Desing size and not User-specified values (in this example, last two columns). Unfortunately, some of them are hard to track, for example design size reheat coil sizing inlet air temperature is neither found in user-specified or autozied values!
  • Unfortunately, some columns have different names compared to field their description. example: {field name: Maximum Hot Water or Steam Flow Rate {m3/s} 0.0, !- Minimum Hot Rate} & {column name: (Desing Size) Maximum Reheat Water Flow Rate}

Additionally, some autosized filed (like Dedicated Outdoor Air High Setpoint Temperature for Design for object sizing:zone cannot be found anywhere!! (I know for my purpose this object should be deleted.)

With all being said, I think I should give up on a general and dry solution and go with manual and dirty one or Steam Flow Rate {m3/s} SPACE5-1 In Node, !- Air Outlet Node Name 0.001, !- Convergence Tolerance NORMAL, !- Damper Heating Action AUTOCALCULATE, !- Maximum Flow per Zone Floor Area During Reheat {m3/s-m2} AUTOCALCULATE; !- Maximum Flow Fraction During Reheat

But in the leave the autozied field be autoszed!!! I should say that I hoped eneryplus with plenty of output summary table mentioned object has seven size columns! I'm reports could provide users a little confused about how to extract sizing results for my code.report for this purpose. I would be extremely thankful for any solution.

How to match the result of autosizing with idf inputs

My purpose is to avoid the auto-sizing of a lot of components after an initial simulation of the model. Since I'm working with several large idf files, it would be very nice to have an automatic and dry solution for this issue. So, using eppy and some existing scripts, I wrote these following lines of code that can get the key value of objects and size values to and modify the idf accordingly.

EDIT:

There is one problem. I can't find the appropriate output report for this purpose. For example, in the AllSummary table report for the AirTerminal:SingleDuct:VAV:Reheat object only 2 autosized values (maxmumn number of 6 is possible) is specified but following table has 10 columns for each row (object):

image description

Below the tables, energyplus report states that:

User-Specified values were used. Design Size values were used if no User-Specified values were provided. Design Size values may be derived from alternate User-Specified values.

Considering the comment, it can be said that:

  • If you fill autosizable fields with your own calculations, energyplus would report both user-specified and autosized values.
  • If you leave autosizable fields blank, energyplus would report autosized values.
  • Some columns are used for size calculation and they are user-specified values from other objects. They will be reported as Desing size and not User-specified values (in this example, last two columns). Unfortunately, some of them are hard to track, for example design size reheat coil sizing inlet air temperature is neither found in user-specified or autozied values!
  • Unfortunately, some columns have different names compared to field their description. example: {field name: Maximum Hot Water or Steam Flow Rate} & {column name: (Desing Size) Maximum Reheat Water Flow Rate}

Additionally, some autosized filed (like Dedicated Outdoor Air High Setpoint Temperature for Design for object sizing:zone cannot be found anywhere!! (I know for my purpose this object should be deleted.)

With all being said, I think I should give up on a general and dry solution and go with manual and dirty one or leave the autozied field be autoszed!!! I should say that I hoped eneryplus with plenty of output reports could provide users a report for this purpose. I would be extremely thankful for any solution.