Buildings.Fluid.Sensors.Conversions.Examples

Information

This package contains examples for the use of models that can be found in Buildings.Fluid.Sensors.Conversions.

Package Content

Name	Description
To_VolumeFraction	Example problem for conversion model

Buildings.Fluid.Sensors.Conversions.Examples.To_VolumeFraction

Information

Modelica definition

model To_VolumeFraction "Example problem for conversion model"
  extends Modelica.Icons.Example;
  package Medium = Buildings.Media.GasesPTDecoupled.SimpleAir(extraPropertiesNames={"CO2"});

  Buildings.Fluid.Sensors.Conversions.To_VolumeFraction conMasVolFra(MMMea=
        Modelica.Media.IdealGases.Common.SingleGasesData.CO2.MM) 
    "Conversion from mass fraction CO2 to volume fraction CO2";
  Modelica.Blocks.Sources.Constant volFra(k=1000E-6) 
    "Set point for volume fraction of 700PPM CO2";
  Buildings.Controls.Continuous.LimPID limPID(
    controllerType=Modelica.Blocks.Types.SimpleController.PI,
    reverseAction=true,
    Ti=600,
    k=2,
    Td=1);
  Buildings.Fluid.Sensors.TraceSubstances senCO2(redeclare package Medium =
        Medium, substanceName="CO2") "CO2 sensor";
  Buildings.Fluid.MixingVolumes.MixingVolume vol(
    nPorts=4,
    redeclare package Medium = Medium,
    V=4*4*2.7,
    C_start={300E-6}*44.009544/28.9651159,
    m_flow_nominal=0.1,
    energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial) "Volume of air";
  Buildings.Fluid.Sources.TraceSubstancesFlowSource souCO2(
    use_m_flow_in=true,
    redeclare package Medium = Medium,
    nPorts=1) "CO2 source";
  Modelica.Blocks.Math.Gain CO2Per(k=15/1000/3600*1.977) 
    "CO2 emission per person";
  Buildings.Fluid.Sources.MassFlowSource_T sou(
    use_m_flow_in=true,
    redeclare package Medium = Medium,
    C={300E-6}*44.009544/28.9651159,
    nPorts=1) "Source of fresh air with 300 PPM CO2";
  Buildings.Fluid.Sources.FixedBoundary sin(
    redeclare package Medium = Medium,
    p=100000,
    C={300E-6}*44.009544/28.9651159,
    nPorts=1) "Sink for exhaust air";
  Modelica.Blocks.Math.Gain gai(k=50/3600) "Gain for mass flow rate";
  Modelica.Blocks.Sources.Constant nPeo(k=1) "Number of people";
  Buildings.Fluid.Sensors.VolumeFlowRate senVolFlo(redeclare package Medium =
        Medium, m_flow_nominal=0.1);
  Modelica.Blocks.Math.Gain norSet(k=1/1000E-6) 
    "Normalization for set point (to scale control input)";
  Modelica.Blocks.Math.Gain norMea(k=1/1000E-6) 
    "Normalization for measured concentration (to scale control input)";
  Modelica.Blocks.Math.Gain conVolFlo(k=3600, y(unit="m3/h")) 
    "Conversion from m3/s to m3/h";
  Buildings.Fluid.Sensors.TraceSubstancesTwoPort senTraSubPeo(m_flow_nominal=0.1,
      redeclare package Medium = Medium,
    C_start=0,
    initType=Modelica.Blocks.Types.Init.InitialState) 
    "CO2 concentration in absorptance from people";
  Buildings.Fluid.Sensors.TraceSubstancesTwoPort senTraSubFre(m_flow_nominal=0.1,
      redeclare package Medium = Medium,
    C_start=0,
    initType=Modelica.Blocks.Types.Init.InitialState) 
    "CO2 concentration in fresh air supply";
  inner Modelica.Fluid.System system;
  Buildings.Fluid.FixedResistances.FixedResistanceDpM res(
    redeclare package Medium = Medium,
    dp_nominal=10,
    m_flow_nominal=50/3600) 
    "Pressure drop to decouple the state of the volume from the state of the boundary condition";
    
equation 

  connect(souCO2.m_flow_in, CO2Per.y);
  connect(gai.y, sou.m_flow_in);
  connect(limPID.y, gai.u);
  connect(nPeo.y, CO2Per.u);
  connect(sou.ports[1], senVolFlo.port_a);
  connect(senCO2.C, conMasVolFra.m);
  connect(conMasVolFra.V, norMea.u);
  connect(norMea.y, limPID.u_m);
  connect(volFra.y, norSet.u);
  connect(norSet.y, limPID.u_s);
  connect(conVolFlo.u, senVolFlo.V_flow);
  connect(souCO2.ports[1], senTraSubPeo.port_a);
  connect(senTraSubPeo.port_b, vol.ports[1]);
  connect(senVolFlo.port_b, senTraSubFre.port_a);
  connect(senTraSubFre.port_b, vol.ports[2]);
  connect(vol.ports[3], senCO2.port);
  connect(vol.ports[4], res.port_a);
  connect(res.port_b, sin.ports[1]);
end To_VolumeFraction;