modelMassFlowSource_WeatherData

Ideal flow source that produces a prescribed mass flow with prescribed trace substances, outside specific enthalpy and mass fraction

Extends from Buildings.Fluid.Sources.BaseClasses.PartialAirSource (Partial component air source with one fluid connector).

Information

Models an ideal flow source, with prescribed values of flow rate and trace substances, with temperature and specific enthalpy from outside:

  • Prescribed mass flow rate.
  • Boundary composition (trace-substance flow).
  • Outside specific enthalpy.
  • Multi-substance composition (e.g. water vapor) from outside.

If use_m_flow_in is false (default option), the m_flow parameter is used as boundary flow rate, and the m_flow_in input connector is disabled; if use_m_flow_in is true, then the m_flow parameter is ignored, and the value provided by the input connector is used instead.

The same applies to the trace substances.

The Buildings.Utilities.Psychrometrics.X_pTphi block is used with the input data including pAtm, TDryBul, relHum from weather bus weaBus, to calculate X.

The same applies to the specific enthalpy.

Note, that boundary temperature, mass fractions and trace substances have only an effect if the mass flow is from the boundary into the port. If mass is flowing from the port into the boundary, the boundary definitions, with exception of boundary flow rate, do not have an effect.

Parameters

TypeNameDefaultDescription
IntegernPorts (from PartialAirSource)0Number of ports
Booleanuse_m_flow_infalseGet the mass flow rate from the input connector
Booleanuse_C_infalseGet the trace substances from the input connector
Modelica.Units.SI.MassFlowRatem_flow0Fixed mass flow rate going out of the fluid port
Medium.ExtraProperty[Medium.nC]Cfill(0, Medium.nC)Fixed values of trace substances
Advanced
BooleanverifyInputs (from PartialAirSource)falseSet to true to stop the simulation with an error if the medium temperature is outside its allowable range

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPorts_b[nPorts]ports (from PartialAirSource)Fluid ports
Modelica.Blocks.Interfaces.RealInputm_flow_inPrescribed mass flow rate
Modelica.Blocks.Interfaces.RealInput[Medium.nC]C_inPrescribed boundary trace substances
Buildings.BoundaryConditions.WeatherData.BusweaBusBus with weather data

Revisions

  • March 11, 2024, by Michael Wetter:
    Corrected use of HideResult.
    This is for #1850.
  • January 09, 2023, by Jianjun Hu:
    Changed base class to constrain medium to moist air.
    This is for IBPSA, #1681.
  • November 14, 2019, by Michael Wetter:
    Removed duplicate connector.
    This is for #1248.
  • January 14, 2019 by Jianjun Hu:
    Changed to extend Buildings.Fluid.Sources.BaseClasses.PartialSource. This is for #1050.
  • May 21, 2017, by Jianjun Hu:
    First implementation. Created flow source with prescribed mass flow and trace substances, outside enthalpy and composition. Weather bus is used. See #777.