Buildings.Examples.ChillerPlant.BaseClasses

Information

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

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

Package Content

Name	Description
SimplifiedRoom	Simplified data center room
WeatherData	Modified WeatherData by adding wet bulb temperature for output
Controls	Package with control components for Buildings.Examples.ChillerPlant

Buildings.Examples.ChillerPlant.BaseClasses.SimplifiedRoom

Information

This is a simplified room model for a data center. There is no heat exchange between the room and ambient environment through the building envelope since it is negligible compared to the heat released by the servers.

Parameters

Type	Name	Default	Description
replaceable package Medium		Modelica.Media.Interfaces.Pa...	Medium model
Length	rooLen		Length of the room [m]
Length	rooWid		Width of the room [m]
Height	rooHei		Height of the room [m]
Power	QRoo_flow		Heat generation of the computer room [W]
MassFlowRate	m_flow_nominal		Nominal mass flow rate [kg/s]

Connectors

Type	Name	Description
replaceable package Medium		Medium model
VesselFluidPorts_b	airPorts[nPorts]	Fluid inlets and outlets

Modelica definition

model SimplifiedRoom "Simplified data center room"
  replaceable package Medium = Modelica.Media.Interfaces.PartialMedium 
    "Medium model";
  parameter Integer nPorts=0 "Number of parts";
  parameter Modelica.SIunits.Length rooLen "Length of the room";
  parameter Modelica.SIunits.Length rooWid "Width of the room";
  parameter Modelica.SIunits.Height rooHei "Height of the room";
  parameter Modelica.SIunits.Power QRoo_flow 
    "Heat generation of the computer room";

  Buildings.Fluid.MixingVolumes.MixingVolume rooVol(
    nPorts=nPorts,
    redeclare each package Medium = Medium,
    V=rooLen*rooWid*rooHei,
    final T_start=293.15,
    m_flow_nominal=m_flow_nominal) "Volume of air in the room";
  Modelica.Fluid.Vessels.BaseClasses.VesselFluidPorts_b airPorts[nPorts](
      redeclare each package Medium = Medium) "Fluid inlets and outlets";
  Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow QSou 
    "Heat source of the room";
  Modelica.Blocks.Sources.Ramp ramp(
    height=QRoo_flow,
    offset=0,
    duration=36000,
    startTime=0);
  parameter Modelica.SIunits.MassFlowRate m_flow_nominal 
    "Nominal mass flow rate";
equation 
  connect(rooVol.ports, airPorts);
  connect(QSou.port, rooVol.heatPort);
  connect(ramp.y, QSou.Q_flow);
end SimplifiedRoom;

Buildings.Examples.ChillerPlant.BaseClasses.WeatherData

Information

This is a modified model of the weather data reader Buildings.BoundaryConditions.WeatherData.ReaderTMY3. It outputs the wet bulb temperature in addition to the other data.

Extends from Buildings.BoundaryConditions.WeatherData.ReaderTMY3 (Reader for TMY3 weather data ).

Parameters

Type	Name	Default	Description
String	filNam		Name of weather data file
Data source
DataSource	pAtmSou	Buildings.BoundaryConditions...	Atmospheric pressure
Pressure	pAtm	101325	Atmospheric pressure (used if pAtmSou=Parameter) [Pa]
DataSource	TDryBulSou	Buildings.BoundaryConditions...	Dry bulb temperature
Temperature	TDryBul	293.15	Dry bulb temperature (used if TDryBul=Parameter) [K]
DataSource	relHumSou	Buildings.BoundaryConditions...	Relative humidity
Real	relHum	0.5	Relative humidity (used if relHum=Parameter)
DataSource	winSpeSou	Buildings.BoundaryConditions...	Wind speed
Velocity	winSpe	1	Wind speed (used if winSpe=Parameter) [m/s]
DataSource	winDirSou	Buildings.BoundaryConditions...	Wind direction
Angle	winDir	1.0	Wind direction (used if winDir=Parameter) [rad]
DataSource	HGloHorSou	Buildings.BoundaryConditions...	Global horizontal radiation
RadiantEnergyFluenceRate	HGloHor	100	Global horizontal radiation (used if HGloHor=Parameter) [W/m2]
DataSource	HDifHorSou	Buildings.BoundaryConditions...	Diffuse horizontal radiation
RadiantEnergyFluenceRate	HDifHor	50	Diffuse horizontal radiation (used if HDifHor=Parameter) [W/m2]
Sky temperature
SkyTemperatureCalculation	calTSky	Buildings.BoundaryConditions...	Computation of black-body sky temperature

Connectors

Type	Name	Description
input RealInput	pAtm_in	Input pressure [Pa]
input RealInput	TDryBul_in	Input dry bulb temperature [K]
input RealInput	relHum_in	Input relative humidity
input RealInput	winSpe_in	Input wind speed [m/s]
input RealInput	winDir_in	Input wind direction [rad]
input RealInput	HGloHor_in	Input global horizontal radiation [W/m2]
input RealInput	HDifHor_in	Input diffuse horizontal radiation [W/m2]
Bus	weaBus	Weather Data Bus

Modelica definition

block WeatherData 
  "Modified WeatherData by adding wet bulb temperature for output"
  extends Buildings.BoundaryConditions.WeatherData.ReaderTMY3;
  Buildings.Utilities.Psychrometrics.TWetBul_TDryBulXi tWetBul_TDryBulXi(
      redeclare package Medium = Buildings.Media.PerfectGases.MoistAir, TDryBul(
        displayUnit="degC"));
equation 
  connect(chePre.POut, tWetBul_TDryBulXi.p);
  connect(tWetBul_TDryBulXi.TWetBul, weaBus.TWetBul);
  connect(cheTemDryBul.TOut, tWetBul_TDryBulXi.TDryBul);
  connect(cheRelHum.relHumOut, tWetBul_TDryBulXi.Xi[1]);
end WeatherData;