packageDefaults

Package with default sizing parameters

Extends from Modelica.Icons.MaterialPropertiesPackage (Icon for package containing property classes).

Information

This package defines some constants that are either

  • typical values used as default parameter values for models inside the package Buildings.Templates, or
  • arbitrary values used for validation purposes only. Those are typically project-specific characteristics (e.g., chiller COP at nominal conditions) and should not be considered as generic default values.

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.TemperatureTChiWatSup7 + 273.15CHW supply temperature (AHRI 551/591)
Modelica.Units.SI.TemperatureTChiWatSup_min3.3 + 273.15Minimum CHW supply temperature (typical)
Modelica.Units.SI.TemperatureTChiWatSup_max16 + 273.15Maximum CHW supply temperature (typical)
Modelica.Units.SI.TemperatureTChiWatRet12 + 273.15CHW return temperature (AHRI 551/591)
Modelica.Units.SI.TemperatureTConWatSup30 + 273.15CW supply temperature (AHRI 551/591)
Modelica.Units.SI.TemperatureTConWatRet35 + 273.15CW return temperature (AHRI 551/591)
Modelica.Units.SI.TemperatureTOutChi35 + 273.15Outdoor air temperature for air-cooled chiller (AHRI 551/591)
Modelica.Units.SI.TemperatureTConEnt_min13 + 273.15Minimum condenser entering fluid temperature (air or water)
Modelica.Units.SI.TemperatureTConEnt_max45 + 273.15Maximum condenser entering fluid temperature (air or water)
Modelica.Units.SI.TemperatureTConLvg_min16 + 273.15Minimum condenser leaving fluid temperature (air or water)
Modelica.Units.SI.TemperatureTConLvg_max50 + 273.15Maximum condenser leaving fluid temperature (air or water)
Modelica.Units.SI.TemperatureTChiWatEcoEnt18 + 273.15WSE entering CHW temperature
Modelica.Units.SI.TemperatureTChiWatEcoLvg11 + 273.15WSE leaving CHW temperature
Modelica.Units.SI.TemperatureTConWatEcoEnt9 + 273.15WSE entering CW temperature
Modelica.Units.SI.TemperatureTConWatEcoLvg16 + 273.15WSE leaving CW temperature
Modelica.Units.SI.TemperatureTOutChiWatLck16 + 273.15Outdoor air lockout temperature below which the CHW system is prevented from operating
Modelica.Units.SI.TemperatureDifferencedTLifChi_min5Minimum chiller lift at minimum load
Modelica.Units.SI.TemperatureTOutDryCooTOutChiDry cooler entering air drybulb temperature
Modelica.Units.SI.TemperatureTWetBulTowEnt24 + 273.15CT entering air wetbulb temperature
RealratPFanByMFloConWatTow340CT fan power divided by CW mass flow rate
RealratMFloConWatByMFloAirTow1.45CT CW mass flow rate divided by air mass flow rate
Modelica.Units.SI.PressureDifferencedpConWatFriTow1E4CW flow-friction losses through open-circuit tower and piping only (without elevation head or valve)
Modelica.Units.SI.PressureDifferencedpConWatStaTow3E4CW elevation head (for open cooling towers only)
Modelica.Units.SI.PressureDifferencedpConWatTowClo5E4CW flow-friction losses through closed-circuit tower and piping only (without valve)
RealratMFloAirByCapChi1E-4Air mass flow rate divided by capacity for air-cooled chiller
RealCOPChiAirCoo2.99Air-cooled chiller COP (ASHRAE 90.1 2022 at 7 °C CHWST, 35 °C OAT)
RealCOPChiWatCoo5.33Water-cooled chiller COP (ASHRAE 90.1 2022 at 7 °C CHWST, 35 °C source LWT)
Modelica.Units.SI.PressureDifferencedpValIso1E3Isolation or bypass valve pressure drop
Modelica.Units.SI.PressureDifferencedpValBypMin3.5E4Minimum flow bypass valve pressure drop at design minimum flow for the largest unit
Modelica.Units.SI.PressureDifferencedpValChe1E4Check valve pressure drop
Modelica.Units.SI.PressureDifferencedpChiWatChi4E4Chiller CHW pressure drop
Modelica.Units.SI.PressureDifferencedpChiWatSet_min5*6894Minimum CHW differential pressure setpoint used in CHW plant reset logic
Modelica.Units.SI.PressureDifferencedpChiWatRemSet_max5E4Maximum CHW differential pressure setpoint remote from the CHW plant
Modelica.Units.SI.PressureDifferencedpChiWatLocSet_max15E4Maximum CHW differential pressure setpoint local to the CHW plant
Modelica.Units.SI.PressureDifferencedpConWatChi4E4Chiller CW pressure drop (water-cooled)
Modelica.Units.SI.PressureDifferencedpAirChi500Chiller air pressure drop across condenser (air-cooled)
Modelica.Units.SI.PressureDifferencedpChiWatEco3E4WSE CHW pressure drop
Modelica.Units.SI.PressureDifferencedpConWatEco3E4WSE CW pressure drop
Modelica.Units.SI.PressureDifferencepChiWat_rel_nominal1.0E5CHW system gauge pressure at design conditions
Modelica.Units.SI.PressureDifferencepHeaWat_rel_nominal2.5E5HHW system gauge pressure at design conditions
Modelica.Units.SI.PressureDifferencedpHeaWatBoi5E3Boiler HW pressure drop
Modelica.Units.SI.TemperatureTHeaWatSup80 + 273.15HW supply temperature
Modelica.Units.SI.TemperatureTHeaWatConSup65 + 273.15HW supply temperature for condensing boilers
Modelica.Units.SI.TemperatureTHeaWatRet55 + 273.15HW return temperature
Modelica.Units.SI.TemperatureTOutHeaWatLck21 + 273.15Outdoor air lockout temperature above which the HW system is prevented from operating
Modelica.Units.SI.PressureDifferencedpHeaWatSet_min5*6894Minimum HW differential pressure setpoint used in HW plant reset logic
Modelica.Units.SI.PressureDifferencedpHeaWatRemSet_max5E4Maximum HW differential pressure setpoint remote from the HW plant
Modelica.Units.SI.PressureDifferencedpHeaWatLocSet_max15E4Maximum HW differential pressure setpoint local to the CHW plant
Modelica.Units.SI.PressureDifferencedpHeaWatHp3E4Heat pump HW pressure drop across condenser barrel
Modelica.Units.SI.TemperatureTHeaWatSupHig60 + 273.15HW supply temperature - High temperature level (AHRI 551/591)
Modelica.Units.SI.TemperatureTHeaWatRetHig50 + 273.15HW return temperature - High temperature level (AHRI 551/591)
Modelica.Units.SI.TemperatureTHeaWatSupMed50 + 273.15HW supply temperature - Medium temperature level (AHRI 551/591)
Modelica.Units.SI.TemperatureTHeaWatRetMed42 + 273.15HW return temperature - Medium temperature level (AHRI 551/591)
Modelica.Units.SI.TemperatureTHeaWatSupLow40 + 273.15HW supply temperature - Low temperature level (AHRI 551/591)
Modelica.Units.SI.TemperatureTHeaWatRetLow35 + 273.15HW return temperature - Low temperature level (AHRI 551/591)
Modelica.Units.SI.TemperatureTOutHpCooTOutChiOutdoor air temperature for air-to-water heat pump rating - Cooling (AHRI 551/591)
Modelica.Units.SI.TemperatureTOutHpHeaHig8 + 273.15Outdoor air temperature for air-to-water heat pump rating - High heating (AHRI 551/591)
Modelica.Units.SI.TemperatureTOutHpHeaLow-8 + 273.15Outdoor air temperature for air-to-water heat pump rating - Low heating (AHRI 551/591)
Modelica.Units.SI.TemperatureTSouHpCoo30 + 273.15Source fluid entering temperature for water-to-water heat pump rating - Cooling (AHRI 551/591)
Modelica.Units.SI.TemperatureTSouHpHea12 + 273.15Source fluid entering temperature for water-to-water heat pump rating - Heating (AHRI 551/591)
RealCOPHpAwHea1.75Air-to-water heat pump heating COP (ASHRAE 90.1 2022 at 50 °C HWST, -8 °C OAT)
RealCOPHpAwCoo2.84Air-to-water heat pump cooling COP (ASHRAE 90.1 2022 at 7 °C CHWST, 35 °C OAT)
RealCOPHpWwHea3.61Water(brine)-to-water heat pump heating COP (ASHRAE 90.1 2022 at 50 °C HWST, 7 °C source LWT)
RealCOPHpWwCoo5.07Water(brine)-to-water heat pump cooling COP (ASHRAE 90.1 2022 at 7 °C CHWST, 35 °C source LWT)
RealratVLiqByCap1E-5Ratio of total fluid volume in hydronic system by installed capacity (ranges from 5 to 30 L/kW)

Revisions

  • November 18, 2022, by Antoine Gautier:
    First implementation.