Buildings.Fluid.Sources.BaseClasses

Information

This package contains base classes that are used to construct the models in Buildings.Fluid.Sources.

Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).

Package Content

Name	Description
Outside	Boundary that takes weather data, and optionally trace substances, as an input

Buildings.Fluid.Sources.BaseClasses.Outside

Information

This is the base class for models that describes boundary conditions for pressure, enthalpy, and species concentration that can be obtained from weather data, and that may be modified based on the wind pressure.

If the parameter use_C_in is false (default option), the C parameter is used as the trace substance for flow that leaves the component, and the C_in input connector is disabled; if use_C_in is true, then the C parameter is ignored, and the value provided by the input connector is used instead.

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 pressure, do not have an effect.

Extends from Modelica.Fluid.Sources.BaseClasses.PartialSource (Partial component source with one fluid connector).

Parameters

Type	Name	Default	Description
replaceable package Medium		PartialMedium	Medium model within the source
Boolean	use_C_in	false	Get the trace substances from the input connector
ExtraProperty	C[Medium.nC]	fill(0, Medium.nC)	Fixed values of trace substances

Connectors

Type	Name	Description
FluidPorts_b	ports[nPorts]
input RealInput	C_in[Medium.nC]	Prescribed boundary trace substances
Bus	weaBus	Bus with weather data

Modelica definition

partial model Outside 
  "Boundary that takes weather data, and optionally trace substances, as an input"
  extends Modelica.Fluid.Sources.BaseClasses.PartialSource;
  parameter Boolean use_C_in = false 
    "Get the trace substances from the input connector";
  parameter Medium.ExtraProperty C[Medium.nC](
       quantity=Medium.extraPropertiesNames)=fill(0, Medium.nC) 
    "Fixed values of trace substances";
  Modelica.Blocks.Interfaces.RealInput C_in[Medium.nC] if use_C_in 
    "Prescribed boundary trace substances";
  Buildings.BoundaryConditions.WeatherData.Bus weaBus "Bus with weather data";
protected 
  final parameter Boolean singleSubstance = ( Medium.nX == 1) 
    "True if single substance medium";
  Buildings.Utilities.Psychrometrics.X_pTphi x_pTphi(
    redeclare package Medium = Medium) if 
       not singleSubstance "Block to compute water vapor concentration";
  Modelica.Blocks.Interfaces.RealInput X_in_internal[Medium.nX] 
    "Needed to connect to conditional connector";
  Modelica.Blocks.Interfaces.RealInput T_in_internal 
    "Needed to connect to conditional connector";
  Modelica.Blocks.Interfaces.RealInput p_in_internal 
    "Needed to connect to conditional connector";
  Modelica.Blocks.Interfaces.RealInput C_in_internal[Medium.nC] 
    "Needed to connect to conditional connector";

equation 
  // Check medium properties
  Modelica.Fluid.Utilities.checkBoundary(Medium.mediumName, Medium.substanceNames,
    Medium.singleState, true, medium.X, "Boundary_pT");

  // Conditional connectors for trace substances
  connect(C_in, C_in_internal);
  if not use_C_in then
    C_in_internal = C;
  end if;
  // Connections to input. This is required to obtain the data from
  // the weather bus in case that the component x_pTphi is conditionally removed
  connect(weaBus.TDryBul, T_in_internal);

  // Connections to compute species concentration
  connect(p_in_internal, x_pTphi.p_in);
  connect(T_in_internal, x_pTphi.T);
  connect(weaBus.relHum, x_pTphi.phi);

  connect(X_in_internal, x_pTphi.X);
  if singleSubstance then
    X_in_internal = zeros(Medium.nX);
  end if;
  // Assign medium properties
  medium.p = p_in_internal;
  medium.T = T_in_internal;
  medium.Xi = X_in_internal[1:Medium.nXi];
  ports.C_outflow = fill(C_in_internal, nPorts);
end Outside;