modelMixedAirHeatMassBalance
Heat and mass balance of the air, assuming completely mixed air
Extends from Buildings.ThermalZones.Detailed.BaseClasses.PartialAirHeatMassBalance (Partial model for heat and mass balance of the air), Buildings.Fluid.Interfaces.LumpedVolumeDeclarations (Declarations for lumped volumes).
Information
This model computes the heat and mass balance of the air. The model assumes a completely mixed air volume.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | NConExt (from ConstructionNumbers) | max(1, nConExt) | Number of elements for exterior constructions |
| Integer | NConExtWin (from ConstructionNumbers) | max(1, nConExtWin) | Number of elements for exterior constructions with windows |
| Integer | NConPar (from ConstructionNumbers) | max(1, nConPar) | Number of elements for partition constructions |
| Integer | NConBou (from ConstructionNumbers) | max(1, nConBou) | Number of elements for constructions that have their outside surface exposed to the boundary of this room |
| Integer | NSurBou (from ConstructionNumbers) | max(1, nSurBou) | Number of elements for surface heat transfer models that connect to constructions that are modeled outside of this room |
| Boolean | haveConExt (from ConstructionNumbers) | nConExt > 0 | Flag to conditionally remove components |
| Boolean | haveConExtWin (from ConstructionNumbers) | nConExtWin > 0 | Flag to conditionally remove components |
| Boolean | haveConPar (from ConstructionNumbers) | nConPar > 0 | Flag to conditionally remove components |
| Boolean | haveConBou (from ConstructionNumbers) | nConBou > 0 | Flag to conditionally remove components |
| Boolean | haveSurBou (from ConstructionNumbers) | nSurBou > 0 | Flag to conditionally remove components |
| ParameterConstruction[NConExt] | datConExt (from ConstructionRecords) | Data for exterior construction | |
| Buildings.ThermalZones.Detailed.BaseClasses.ParameterConstructionWithWindow[NConExtWin] | datConExtWin (from ConstructionRecords) | Data for exterior construction with window | |
| Buildings.ThermalZones.Detailed.BaseClasses.ParameterConstruction[NConPar] | datConPar (from ConstructionRecords) | Data for partition construction | |
| Buildings.ThermalZones.Detailed.BaseClasses.ParameterConstruction[NConBou] | datConBou (from ConstructionRecords) | Data for construction boundary | |
| Buildings.ThermalZones.Detailed.BaseClasses.OpaqueSurface[NSurBou] | surBou (from ConstructionRecords) | Record for data of surfaces whose heat conduction is modeled outside of this room | |
| HeatTransfer.Data.OpaqueConstructions.Brick120 | dummyCon (from ConstructionRecords) | Dummy construction to assign a parameter to the instance | |
| Buildings.HeatTransfer.Data.GlazingSystems.SingleClear3 | dummyGlaSys (from ConstructionRecords) | Dummy construction to assign a parameter to the instance | |
| Boolean | haveShade (from PartialAirHeatMassBalance) | Set to true if at least one window has an interior or exterior shade | |
| Modelica.Units.SI.Volume | V (from PartialAirHeatMassBalance) | Volume | |
| Boolean | homotopyInitialization | true | = true, use homotopy method |
| Exterior constructions | |||
| Integer | nConExt (from ConstructionNumbers) | Number of exterior constructions | |
| Integer | nConExtWin (from ConstructionNumbers) | Number of window constructions | |
| Partition constructions | |||
| Integer | nConPar (from ConstructionNumbers) | Number of partition constructions | |
| Boundary constructions | |||
| Integer | nConBou (from ConstructionNumbers) | Number of constructions that have their outside surface exposed to the boundary of this room | |
| Integer | nSurBou (from ConstructionNumbers) | Number of surface heat transfer models that connect to constructions that are modeled outside of this room | |
| General › Ports | |||
| Integer | nPorts (from PartialAirHeatMassBalance) | 0 | Number of ports |
| Dynamics › Conservation equations | |||
| Modelica.Fluid.Types.Dynamics | energyDynamics (from LumpedVolumeDeclarations) | Modelica.Fluid.Types.Dynamics.DynamicFreeInitial | Type of energy balance: dynamic (3 initialization options) or steady state |
| Modelica.Fluid.Types.Dynamics | substanceDynamics (from LumpedVolumeDeclarations) | energyDynamics | Type of independent mass fraction balance: dynamic (3 initialization options) or steady state |
| Modelica.Fluid.Types.Dynamics | traceDynamics (from LumpedVolumeDeclarations) | energyDynamics | Type of trace substance balance: dynamic (3 initialization options) or steady state |
| Advanced › Dynamics | |||
| Modelica.Fluid.Types.Dynamics | massDynamics (from LumpedVolumeDeclarations) | energyDynamics | Type of mass balance: dynamic (3 initialization options) or steady state, must be steady state if energyDynamics is steady state |
| Initialization | |||
| Medium.AbsolutePressure | p_start (from LumpedVolumeDeclarations) | Medium.p_default | Start value of pressure |
| Medium.Temperature | T_start (from LumpedVolumeDeclarations) | Medium.T_default | Start value of temperature |
| Medium.MassFraction[Medium.nX] | X_start (from LumpedVolumeDeclarations) | Medium.X_default | Start value of mass fractions m_i/m |
| Medium.ExtraProperty[Medium.nC] | C_start (from LumpedVolumeDeclarations) | fill(0, Medium.nC) | Start value of trace substances |
| Medium.ExtraProperty[Medium.nC] | C_nominal (from LumpedVolumeDeclarations) | fill(1E-2, Medium.nC) | Nominal value of trace substances. (Set to typical order of magnitude.) |
| Dynamics | |||
| Real | mSenFac (from LumpedVolumeDeclarations) | 1 | Factor for scaling the sensible thermal mass of the volume |
| Nominal condition | |||
| Modelica.Units.SI.MassFlowRate | m_flow_nominal | Nominal mass flow rate | |
| Convective heat transfer | |||
| Buildings.HeatTransfer.Types.InteriorConvection | conMod | Convective heat transfer model for opaque constructions | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | hFixed | Constant convection coefficient for opaque constructions | |
| Ports | |||
| Boolean | use_C_flow | Set to true to enable input connector for trace substance | |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput[NConExtWin] | uSha (from PartialAirHeatMassBalance) | Input connector, used to scale the surface area to take into account an operable shading device, 0: unshaded; 1: fully shaded | |
| Modelica.Blocks.Interfaces.RealInput[NConExtWin] | QRadAbs_flow (from PartialAirHeatMassBalance) | Total net radiation that is absorbed by the shade (positive if absorbed) | |
| Modelica.Blocks.Interfaces.RealInput | QCon_flow (from PartialAirHeatMassBalance) | Convective sensible heat gains of the room | |
| Modelica.Blocks.Interfaces.RealInput | QLat_flow (from PartialAirHeatMassBalance) | Latent heat gains for the room | |
| Modelica.Blocks.Interfaces.RealOutput[NConExtWin] | TSha (from PartialAirHeatMassBalance) | Shade temperature | |
| Modelica.Fluid.Vessels.BaseClasses.VesselFluidPorts_b[nPorts] | ports (from PartialAirHeatMassBalance) | Fluid inlets and outlets | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heaPorAir (from PartialAirHeatMassBalance) | Heat port to air volume | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConExt] | conExt (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface of exterior constructions | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConExtWin] | conExtWin (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface of exterior constructions that contain a window | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConExtWin] | glaUns (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface of unshaded glass | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConExtWin] | glaSha (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface of shaded glass | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConExtWin] | conExtWinFra (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface of window frame | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConPar] | conPar_a (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface a of partition constructions | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConPar] | conPar_b (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface b of partition constructions | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NConBou] | conBou (from PartialAirHeatMassBalance) | Heat port that connects to room-side surface of constructions that expose their other surface to the outside | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[NSurBou] | conSurBou (from PartialAirHeatMassBalance) | Heat port to surfaces of models that compute the heat conduction outside of this room | |
| Modelica.Blocks.Interfaces.RealInput[Medium.nC] | C_flow | Trace substance mass flow rate added to the room air. Enable if use_C_flow = true |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Fluid.MixingVolumes.MixingVolumeMoistAir | vol | Room air volume | |
| HeatTransfer.Convection.Interior[NConExt] | convConExt | Convective heat transfer | |
| HeatTransfer.Convection.Interior[NConExtWin] | convConExtWin | Convective heat transfer | |
| HeatTransfer.Windows.InteriorHeatTransferConvective[NConExtWin] | convConWin | Model for convective heat transfer at window | |
| HeatTransfer.Convection.Interior[nConPar] | convConPar_a | Convective heat transfer | |
| HeatTransfer.Convection.Interior[nConPar] | convConPar_b | Convective heat transfer | |
| HeatTransfer.Convection.Interior[nConBou] | convConBou | Convective heat transfer | |
| HeatTransfer.Convection.Interior[nSurBou] | convSurBou | Convective heat transfer |
Revisions
-
April 14, 2020, by Michael Wetter:
ChangedhomotopyInitializationto a constant.
This is for IBPSA, #1341. -
April 8, 2019, by Michael Wetter:
Propagated parametermSenFac.
This is for issue Buildings #1405. -
December 14, 2018, by Michael Wetter:
Replaced call toMedium.enthalpyOfCondensingGaswithBuildings.Media.Air.enthalpyOfCondensingGas.
This is for issue Buildings #1285. -
April 12, 2017, by Michael Wetter:
Removed temperature connection that is no longer needed.
This is for issue Buildings #704. -
May 2, 2016, by Michael Wetter:
Refactored implementation of latent heat gain. This is for issue 515. -
March 2, 2015, by Michael Wetter:
Refactored model to allow a temperature dependent convective heat transfer on the room side. This is for issue 52. -
July 17, 2013, by Michael Wetter:
Separated the model into a partial base class and a model that uses the mixed air assumption. -
July 12, 2013, by Michael Wetter:
First implementation to facilitate the implementation of non-uniform room air models.