Buildings.Fluid.HeatExchangers.CoolingTowers.Examples.BaseClasses

Information

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

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

Package Content

Name	Description
PartialStaticTwoPortCoolingTower	Base class for test models of cooling towers
PartialStaticTwoPortCoolingTowerWetBulb	Partial test model for cooling tower with wet bulb temperature as potential for heat transfer

Buildings.Fluid.HeatExchangers.CoolingTowers.Examples.BaseClasses.PartialStaticTwoPortCoolingTower

Parameters

Type	Name	Default	Description
CoolingTower	tow	redeclare Buildings.Fluid.He...	Cooling tower
Nominal condition
MassFlowRate	mWat_flow_nominal	0.5	Design air flow rate [kg/s]

Connectors

Type	Name	Description
Bus	weaBus

Modelica definition

partial model PartialStaticTwoPortCoolingTower 
  "Base class for test models of cooling towers"
  import Buildings;

 package Medium_W = Buildings.Media.ConstantPropertyLiquidWater;

  parameter Modelica.SIunits.MassFlowRate mWat_flow_nominal = 0.5 
    "Design air flow rate";

  replaceable Buildings.Fluid.HeatExchangers.CoolingTowers.BaseClasses.CoolingTower
                                                                          tow
     constrainedby 
    Buildings.Fluid.HeatExchangers.CoolingTowers.BaseClasses.CoolingTower(
    redeclare package Medium = Medium_W,
    m_flow_nominal=mWat_flow_nominal,
    dp_nominal=6000,
    energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyState) "Cooling tower";
  Buildings.Fluid.Movers.FlowMachine_m_flow pum(redeclare package Medium =
        Medium_W, m_flow_nominal=mWat_flow_nominal,
    dynamicBalance=false,
    filteredSpeed=false) "Pump for chilled water loop";
  inner Modelica.Fluid.System system;
  Buildings.BoundaryConditions.WeatherData.ReaderTMY3 weaDat(filNam=
        "Resources/weatherdata/USA_CA_San.Francisco.Intl.AP.724940_TMY3.mos");
  Buildings.BoundaryConditions.WeatherData.Bus weaBus;
  Modelica.Blocks.Logical.OnOffController onOffController(bandwidth=4);
  Modelica.Blocks.Logical.Switch switch1;
  Modelica.Blocks.Sources.Constant TSwi(k=273.15 + 22) 
    "Switch temperature for switching tower pump on";
  Modelica.Blocks.Sources.Constant zer(k=0) "Zero flow rate";
  Modelica.Blocks.Sources.Constant mWat_flow(k=mWat_flow_nominal) 
    "Water flow rate";
  Buildings.Fluid.MixingVolumes.MixingVolume vol(nPorts=3,
    redeclare package Medium = Medium_W,
    m_flow_nominal=mWat_flow_nominal,
    prescribedHeatFlowRate=true,
    V=0.5);
  Buildings.Fluid.Sources.FixedBoundary   exp(           redeclare package
      Medium = Medium_W, nPorts=1);
  Modelica.Thermal.HeatTransfer.Sources.FixedHeatFlow fixHeaFlo(Q_flow=0.5*
        mWat_flow_nominal*4200*5) "Fixed heat flow rate";
  Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor TVol 
    "Water temperature";
equation 
  connect(weaDat.weaBus, weaBus);
  connect(onOffController.y, switch1.u2);
  connect(zer.y, switch1.u3);
  connect(mWat_flow.y, switch1.u1);
  connect(vol.ports[1], pum.port_a);
  connect(fixHeaFlo.port, vol.heatPort);
  connect(vol.heatPort, TVol.port);
  connect(tow.port_b, vol.ports[2]);
  connect(pum.port_b, tow.port_a);
  connect(onOffController.u, TSwi.y);
  connect(TVol.T, onOffController.reference);
  connect(switch1.y, pum.m_flow_in);
  connect(exp.ports[1], vol.ports[3]);
end PartialStaticTwoPortCoolingTower;

Buildings.Fluid.HeatExchangers.CoolingTowers.Examples.BaseClasses.PartialStaticTwoPortCoolingTowerWetBulb

Information

Parameters

Type	Name	Default	Description
CoolingTower	tow	redeclare Buildings.Fluid.He...	Cooling tower
Nominal condition
MassFlowRate	mWat_flow_nominal	0.5	Design air flow rate [kg/s]

Connectors

Type	Name	Description
Bus	weaBus

Modelica definition

model PartialStaticTwoPortCoolingTowerWetBulb 
  "Partial test model for cooling tower with wet bulb temperature as potential for heat transfer"
  import Buildings;
  extends PartialStaticTwoPortCoolingTower(exp(redeclare package Medium =
          Medium_W));
 package Medium_A = Buildings.Media.PerfectGases.MoistAir;
  Buildings.Utilities.Psychrometrics.TWetBul_TDryBulXi wetBulTem(
                                                        redeclare package
      Medium = Medium_A) "Model for wet bulb temperature";
equation 
  connect(weaBus.relHum, wetBulTem.Xi[1]);
  connect(weaBus.pAtm, wetBulTem.p);
  connect(weaBus.TDryBul, wetBulTem.TDryBul);
end PartialStaticTwoPortCoolingTowerWetBulb;