Engineering Reference — EnergyPlus 8.2

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Sizing Manager[LINK]

The sizing calculations in EnergyPlus are managed by a sizing manager contained in the software module SizingManager. The main sizing manager routine ManageSizing is called from ManageSimulation before the annual simulation sequence is invoked. ManageSizing performs the following tasks.

By calling GetSizingParams, GetZoneSizingInput, GetSystemSizingInput and GetPlantSizingInput reads in all the user sizing input contained in objects Sizing:Parameters, Sizing:Zone, Sizing:System and Sizing:Plant. These objects and their data are described in the EnergyPlus Input Output Reference, Group - Design Objects.

Set the ZoneSizingCalc flag equal to true.

Loop over all the sizing periods by each day. This starts the zone design calculations.

Call UpdateZoneSizing(BeginDay) to initialize zone design load and flow rate sequences.

Loop over hours in the day

Loop over zone time steps in each hour

Call ManageWeather to obtain outside conditions for this time-step.

Call ManageHeatBalance to do a full heat balance calculation for each zone. The call to ManageHeatBalance also brings about an HVAC simulation. ZoneSizingCalc = true signals the HVACManager to ignore the real HVAC system and instead run the ideal zonal system (described below) used to calculate design loads and flow rates. HVACManager also calls UpdateZoneSizing(DuringDay) to save the results of the ideal zonal system calculation in the design load and flow rate sequences.

Call UpdateZoneSizing(EndDay) to calculate peaks and moving averages from the zone design sequences for each design day.

Call UpdateZoneSizing(EndZoneSizingCalc) to calculate for each zone the peak heating & cooling loads and flow rates over all the sizing periods (design days and sizing periods from the weather file, if specified). The corresponding design load and flow rate sequences are saved for use in the system design calculations. This ends the zone design calculations.

Set the SysSizingCalc flag equal to true.

Call ManageZoneEquipment and ManageAirLoops to read in the zone and central system inputs needed for the system design calculations. The program needs enough information to be able to figure out the overall air loop connectivity.

Loop over all the sizing periods by each day. This starts the system design calculations.

Call UpdateSysSizing(BeginDay) to initialize system design load and flow rate sequences.

Loop over hours in the day

Loop over zone time steps in each hour

Call ManageWeather to obtain outside conditions for this time-step.

Call UpdateSysSizing(DuringDay) to save the results of the system design calculations in the system design load and flow rate sequences.

Call UpdateSysSizing(EndDay) to calculate peaks and moving averages from the system design sequences for each sizing period.

Call UpdateSysSizing(EndSysSizingCalc)) to calculate for each system the peak heating & cooling loads and flow rates over all the sizing periods (design days and sizing periods from the weather file, if specified). The corresponding design load and flow rate sequences are saved for use in the component sizing calculations. This ends the system design calculations.

And this ends the tasks of the Sizing Manager.