Buildings.BoundaryConditions.WeatherData.BaseClasses

Information

This package contains base classes that are used to construct the models in Buildings.BoundaryConditions.WeatherData.

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

Package Content

Name	Description
CheckCeilingHeight	Ensures that the ceiling height is above a lower bound
CheckRadiation	Ensure that the radiation is not smaller than 0
CheckRelativeHumidity	Check the validity of relative humidity
CheckPressure	Ensures that the interpolated pressure is between prescribed bounds
CheckSkyCover	Constrains the sky cover to [0, 1]
CheckTemperature	Check the validity of temperature data
CheckWindDirection	Constrains the wind direction to [0, 2*pi] degree
CheckWindSpeed	Ensures that the wind speed is non-negative
ConvertRadiation	Convert the unit of solar radiation received from the TMY3 data file
ConvertRelativeHumidity	Convert the relative humidity from percentage to real
ConvertTime	Converts the simulation time to calendar time in scale of 1 year (365 days)
EquationOfTime	Equation of time
LocalCivilTime	Converts the clock time to local civil time.
SolarTime	Solar time
getHeaderElementTMY3	Gets an element from the header of a TMY3 weather data file
getLongitudeTMY3	Gets the longitude from a TMY3 weather data file
getTimeZoneTMY3	Gets the time zone from a TMY3 weather data file
Examples	Collection of models that illustrate model use and test models

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckCeilingHeight

Information

This component ensures that the ceiling height is at least 0 meters.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	ceiHeiIn	Input ceiling height [m]
output RealOutput	ceiHeiOut	Ceiling height [m]

Modelica definition

block CheckCeilingHeight 
  "Ensures that the ceiling height is above a lower bound"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput ceiHeiIn(final quantity="Height", final unit=
           "m") "Input ceiling height";
  Modelica.Blocks.Interfaces.RealOutput ceiHeiOut(final quantity="Height",
      final unit="m") "Ceiling height";
  constant Modelica.SIunits.Height ceiHeiMin=0 "Minimum allowed ceiling height";
equation 

  ceiHeiOut = Buildings.Utilities.Math.Functions.smoothMax(
    ceiHeiIn,
    ceiHeiMin,
    0.1);

end CheckCeilingHeight;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckRadiation

Information

This component ensures that the radiation is not smaller than 0. Modelica Table will interpolate data when it reads the data from a file. Thus, it is possible to generate negative value due to the interpolation.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	HIn	Input radiation [W/m2]
output RealOutput	HOut	Radiation [W/m2]

Modelica definition

block CheckRadiation 
  "Ensure that the radiation is not smaller than 0"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput HIn(final quantity=
        "RadiantEnergyFluenceRate", final unit="W/m2") "Input radiation";
  Modelica.Blocks.Interfaces.RealOutput HOut(final quantity=
        "RadiantEnergyFluenceRate", final unit="W/m2") "Radiation";

  constant Modelica.SIunits.RadiantEnergyFluenceRate HMin=0.0001 
    "Minimum value for radiation";
equation 

  HOut = Buildings.Utilities.Math.Functions.smoothMax(
    x1=HIn,
    x2=HMin,
    deltaX=HMin/10);
end CheckRadiation;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckRelativeHumidity

Information

This component constrains the value of relative humidity to a range of [0, 1].

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	relHumIn	Input relative humidity [1]
output RealOutput	relHumOut	Relative humidity [1]

Modelica definition

block CheckRelativeHumidity "Check the validity of relative humidity"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput relHumIn(final unit="1") 
    "Input relative humidity";
  Modelica.Blocks.Interfaces.RealOutput relHumOut(final unit="1") 
    "Relative humidity";
  constant Real delta=0.01 "Smoothing parameter";
protected 
  constant Real relHumMin=delta "Lower bound";
  constant Real relHumMax=1 - delta "Upper bound";

equation 
  relHumOut = Buildings.Utilities.Math.Functions.smoothLimit(
    relHumIn,
    relHumMin,
    relHumMax,
    delta/10);
end CheckRelativeHumidity;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckPressure

Information

This component ensures that the interpolated pressure is between 31,000 Pa and 120,000 Pa.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	PIn	Input pressure [Pa]
output RealOutput	POut	Atmospheric pressure [Pa]

Modelica definition

block CheckPressure 
  "Ensures that the interpolated pressure is between prescribed bounds"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput PIn(final quantity="Pressure", final unit=
           "Pa") "Input pressure";
  Modelica.Blocks.Interfaces.RealOutput POut(final quantity="Pressure", final unit=
           "Pa") "Atmospheric pressure";
  constant Modelica.SIunits.Pressure PMin=3100 "Minimum allowed pressure";
  constant Modelica.SIunits.Pressure PMax=120000 "Maximum allowed pressure";
equation 
  assert(PIn > PMin, "Pressure out of bounds.\n" + "   PIn = " + String(PIn));
  assert(PIn < PMax, "Pressure out of bounds.\n" + "   PIn = " + String(PIn));
  POut = PIn;

end CheckPressure;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckSkyCover

Information

This component constrains the interpolated sky cover between 0 and 10.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	nIn	Input sky cover [0, 10]
output RealOutput	nOut	Sky cover [0, 10] [1]

Modelica definition

block CheckSkyCover "Constrains the sky cover to [0, 1]"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput nIn "Input sky cover [0, 10]";
  Modelica.Blocks.Interfaces.RealOutput nOut(unit="1") "Sky cover [0, 10]";

  constant Real delta=0.01 "Smoothing parameter";
protected 
  constant Real nMin=delta "Lower bound";
  constant Real nMax=10 - delta "Upper bound";
equation 
  nOut = Buildings.Utilities.Math.Functions.smoothLimit(
    nIn,
    nMin,
    nMax,
    delta/10)/10;
end CheckSkyCover;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckTemperature

Information

This component checks the value of temperature. If the temperature is outside TMin and TMax, the simulation will stop with an error.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Parameters

Type	Name	Default	Description
Temperature	TMin	203.15	Minimum allowed temperature [K]
Temperature	TMax	343.15	Maximum allowed temperature [K]

Connectors

Type	Name	Description
input RealInput	TIn	Input Temperature [K]
output RealOutput	TOut	Output temperature [K]

Modelica definition

block CheckTemperature "Check the validity of temperature data"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput TIn(
    final quantity="Temperature",
    final unit="K",
    displayUnit="degC") "Input Temperature";
  Modelica.Blocks.Interfaces.RealOutput TOut(
    final quantity="Temperature",
    final unit="K",
    displayUnit="degC") "Output temperature";

  parameter Modelica.SIunits.Temperature TMin(displayUnit="degC") = 203.15 
    "Minimum allowed temperature";
  parameter Modelica.SIunits.Temperature TMax(displayUnit="degC") = 343.15 
    "Maximum allowed temperature";

equation 
  TOut = TIn;
  assert(TOut > TMin, "Temperature out of bounds.\n" + "   TOut = " + String(
    TOut));
  assert(TOut < TMax, "Temperature out of bounds.\n" + "   TOut = " + String(
    TOut));

end CheckTemperature;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckWindDirection

Information

This component constrains the interpolated wind direction between 0 and 360 degree.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	nIn	Input wind direction [rad]
output RealOutput	nOut	Wind direction [rad]

Modelica definition

block CheckWindDirection 
  "Constrains the wind direction to [0, 2*pi] degree"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput nIn(
    final quantity="Angle",
    final unit="rad",
    displayUnit="deg") "Input wind direction";
  Modelica.Blocks.Interfaces.RealOutput nOut(
    final quantity="Angle",
    final unit="rad",
    displayUnit="deg") "Wind direction";

  constant Real delta=0.01 "Smoothing parameter";
protected 
  constant Real nMin=0 "Lower bound";
  constant Real nMax=2*Modelica.Constants.pi "Upper bound";
equation 

  nOut = Buildings.Utilities.Math.Functions.smoothLimit(
    nIn,
    nMin,
    nMax,
    delta/10);
end CheckWindDirection;

Buildings.BoundaryConditions.WeatherData.BaseClasses.CheckWindSpeed

Information

This component ensures that the wind speed is non-negative.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	winSpeIn	Input wind speed [m/s]
output RealOutput	winSpeOut	Wind speed [m/s]

Modelica definition

block CheckWindSpeed "Ensures that the wind speed is non-negative"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput winSpeIn(final quantity="Velocity",
      final unit="m/s") "Input wind speed";
  Modelica.Blocks.Interfaces.RealOutput winSpeOut(final quantity="Velocity",
      final unit="m/s") "Wind speed";
  constant Modelica.SIunits.Velocity winSpeMin=1e-6 
    "Minimum allowed wind speed";

equation 
  // Modelica Table will interpolate data when it reads the weather data file.
  // It can generate negative values due to the interpolation.
  winSpeOut = Buildings.Utilities.Math.Functions.smoothMax(
    x1=winSpeIn,
    x2=winSpeMin,
    deltaX=winSpeMin/10);

end CheckWindSpeed;

Buildings.BoundaryConditions.WeatherData.BaseClasses.ConvertRadiation

Information

The TMY3 data for solar radiation is the radiation accumulated in one hour. Thus, it used a unit of Wh/m2. This component converts Wh/m2 to W/m2 that is the standard unit in Modelica.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	HIn	Input radiation [W.h/m2]
output RealOutput	HOut	Radiation [W/m2]

Modelica definition

block ConvertRadiation 
  "Convert the unit of solar radiation received from the TMY3 data file"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput HIn(final unit="W.h/m2") 
    "Input radiation";
  Modelica.Blocks.Interfaces.RealOutput HOut(final quantity=
        "RadiantEnergyFluenceRate", final unit="W/m2") "Radiation";

protected 
  constant Modelica.SIunits.Time Hou=3600 "1 hour";

equation 
  HOut = HIn/Modelica.SIunits.Conversions.to_hour(Hou);
end ConvertRadiation;

Buildings.BoundaryConditions.WeatherData.BaseClasses.ConvertRelativeHumidity

Information

This component converts the relative humidity from percentage to real. Input is the relative humidity in percentage, as this is the data format that is used in the Typical Meteorological Year weather data.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	relHumIn	Value of relative humidity in percentage [1]
output RealOutput	relHumOut	Relative humidity between 0 and 1 [1]

Modelica definition

block ConvertRelativeHumidity 
  "Convert the relative humidity from percentage to real"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput relHumIn(unit="1") 
    "Value of relative humidity in percentage";
  Modelica.Blocks.Interfaces.RealOutput relHumOut(unit="1") 
    "Relative humidity between 0 and 1";
equation 
  relHumOut = relHumIn/100;
end ConvertRelativeHumidity;

Buildings.BoundaryConditions.WeatherData.BaseClasses.ConvertTime

Information

This component converts the simulation time to calendar time in a scale of 1 year (365 days).

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	simTim	Simulation time [s]
output RealOutput	calTim	Calendar time [s]

Modelica definition

block ConvertTime 
  "Converts the simulation time to calendar time in scale of 1 year (365 days)"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput simTim(final quantity="Time", final unit=
       "s") "Simulation time";
  Modelica.Blocks.Interfaces.RealOutput calTim(final quantity="Time", final 
      unit="s") "Calendar time";

protected 
  constant Modelica.SIunits.Time year=31536000 "Number of seconds in a year";
  discrete Modelica.SIunits.Time tStart "Start time of period";
  //Integer count "Period count";

initial algorithm 
  tStart := integer(simTim/year)*year;
equation 
  when simTim - pre(tStart) > year then
    tStart = integer(simTim/year)*year;
  end when;
  calTim = simTim - tStart;
end ConvertTime;

Buildings.BoundaryConditions.WeatherData.BaseClasses.EquationOfTime

Information

This component computes the difference between solar noon and noon of local civic time.

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	nDay	Zero-based day number in seconds (January 1=0, January 2=86400) [s]
output RealOutput	eqnTim	Equation of time [s]

Modelica definition

block EquationOfTime "Equation of time"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput nDay(quantity="Time", unit="s") 
    "Zero-based day number in seconds (January 1=0, January 2=86400)";
  Modelica.Blocks.Interfaces.RealOutput eqnTim(
    final quantity="Time",
    final unit="s",
    displayUnit="min") "Equation of time";
protected 
  Real Bt;
equation 
  Bt = Modelica.Constants.pi*((nDay + 86400)/86400 - 81)/182 
    "Our unit is s instead of day in (A.4.2b)";
  eqnTim = 60*(9.87*Modelica.Math.sin(2*Bt) - 7.53*Modelica.Math.cos(Bt) - 1.5*
    Modelica.Math.sin(Bt)) "Our unit is s instead of min in (A.4.2a)";
end EquationOfTime;

Buildings.BoundaryConditions.WeatherData.BaseClasses.LocalCivilTime

Information

This component converts the clock time to local civil time. The parameter timZon represents the time zone of the facility (relative to Greenwich Mean Time or the 0th meridian). Time zones west of GMT (e.g. North America) are represented as negative; east of GMT as positive. Fraction of hours are represented in decimals (e.g. for 6:30, use 6.5).

The formula is based on Michael Wetter's thesis (A4.1):

  locTim = greTim + (lon*180/pi)*86400/360 = cloTim - timZon + lon*43200/pi 

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Parameters

Type	Name	Default	Description
Time	timZon		Time zone [s]
Angle	lon		Longitude [rad]

Connectors

Type	Name	Description
input RealInput	cloTim	Clock time [s]
output RealOutput	locTim	Local civil time [s]

Modelica definition

block LocalCivilTime "Converts the clock time to local civil time."
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput cloTim(final quantity="Time", final unit=
       "s") "Clock time";
  parameter Modelica.SIunits.Time timZon(displayUnit="h") "Time zone";
  parameter Modelica.SIunits.Angle lon(displayUnit="deg") "Longitude";
  Modelica.Blocks.Interfaces.RealOutput locTim(final quantity="Time", final unit=
           "s") "Local civil time";

equation 
  locTim = cloTim - timZon + lon*43200/Modelica.Constants.pi;

end LocalCivilTime;

Buildings.BoundaryConditions.WeatherData.BaseClasses.SolarTime

Information

This component computes the local solar time. (Note: To avoid events, it does not convert solar time in a scale of 24 hours.)

Extends from Modelica.Blocks.Interfaces.BlockIcon (Basic graphical layout of input/output block).

Connectors

Type	Name	Description
input RealInput	locTim	Local time [s]
input RealInput	equTim	Equation of time [s]
output RealOutput	solTim	Solar time [s]

Modelica definition

block SolarTime "Solar time"
  extends Modelica.Blocks.Interfaces.BlockIcon;
public 
  Modelica.Blocks.Interfaces.RealInput locTim(quantity="Time", unit="s") 
    "Local time";
  Modelica.Blocks.Interfaces.RealInput equTim(quantity="Time", unit="s") 
    "Equation of time";
  Modelica.Blocks.Interfaces.RealOutput solTim(
    final quantity="Time",
    final unit="s",
    displayUnit="s") "Solar time";
algorithm 
  solTim := locTim + equTim "Our unit is s in stead of h in (A.4.3)";

end SolarTime;

Buildings.BoundaryConditions.WeatherData.BaseClasses.getHeaderElementTMY3

Information

start

Inputs

Type	Name	Default	Description
String	filNam		Name of weather data file
String	start		Start of the string that contains the elements
String	name	"longitude"	Name of data element, used in error reporting
Integer	position		Position of the element on the line that contains 'start'

Outputs

Type	Name	Description
String	element	Element at position 'pos' of the line that starts with 'start'

Modelica definition

function getHeaderElementTMY3 
  "Gets an element from the header of a TMY3 weather data file"
 input String filNam "Name of weather data file";
 input String start "Start of the string that contains the elements";
 input String name = "longitude" 
    "Name of data element, used in error reporting";
 input Integer position(min=1) 
    "Position of the element on the line that contains 'start'";
 output String element 
    "Element at position 'pos' of the line that starts with 'start'";
protected 
 String lin "Line that is used in parser";
 Integer iLin "Line number";
 Integer index "Index of string #LOCATION";
 Integer staInd "Start index used when parsing a real number";
 Integer nexInd "Next index used when parsing a real number";
 Boolean found "Flag, true if #LOCATION has been found";
 Boolean EOF "Flag, true if EOF has been reached";
 String fouDel "Found delimiter";
algorithm 
  // Get line that starts with 'start'
  iLin :=0;
  EOF :=false;
  while (not EOF) and (index == 0) loop
    iLin:=iLin + 1;
    (lin, EOF) :=Modelica.Utilities.Streams.readLine(fileName=filNam,
      lineNumber=iLin);
    index :=Modelica.Utilities.Strings.find(
      string=lin,
      searchString=start,
      startIndex=1,
      caseSensitive=false);
  end while;
  assert(not EOF, "Error: Did not find '" + start + "' when scanning the weather file."
                      + "\n   Check for correct weather file syntax.");
  // Loop over the tokens until the position is reached
  nexInd :=1;
  for i in 1:position-1 loop
  nexInd :=Modelica.Utilities.Strings.find(
      string=lin,
      searchString=  ",",
      startIndex=nexInd+1);
   assert(nexInd > 0, "Error when scanning weather file. Not enough tokens to find " + name + "."
         + "\n   Check for correct file syntax." + "\n   The scanned line is '" +
        lin + "'.");
  end for;
  staInd := nexInd;
  // Find the next delimiter
  nexInd :=Modelica.Utilities.Strings.find(
      string=lin,
      searchString=  ",",
      startIndex=nexInd+1);
  assert(nexInd > 0, "Error when scanning weather file. Not enough tokens to find " + name + "."
         + "\n   Check for correct file syntax." + "\n   The scanned line is '" +
         lin + "'.");
  // Get the element
  element :=Modelica.Utilities.Strings.substring(lin, startIndex=staInd+1, endIndex=nexInd-1);
end getHeaderElementTMY3;

Buildings.BoundaryConditions.WeatherData.BaseClasses.getLongitudeTMY3

Information

Inputs

Type	Name	Default	Description
String	filNam		Name of weather data file

Outputs

Type	Name	Description
Angle	lon	Longitude from the weather file [rad]

Modelica definition

function getLongitudeTMY3 
  "Gets the longitude from a TMY3 weather data file"
 input String filNam "Name of weather data file";
 output Modelica.SIunits.Angle lon "Longitude from the weather file";
protected 
 Integer nexInd "Next index, used for error handling";
 String element "String representation of the returned element";
algorithm 
  element :=
    Buildings.BoundaryConditions.WeatherData.BaseClasses.getHeaderElementTMY3(
      filNam=filNam,
      start="#LOCATION",
      name=  "longitude",
      position=8);
   (nexInd, lon) :=Modelica.Utilities.Strings.Advanced.scanReal(
    string=element,
    startIndex=1,
    unsigned=false);
   assert(nexInd > 1, "Error when converting the longitude '" +
                      element + "' from a String to a Real.");
   // Convert from degree to rad
   lon :=lon*Modelica.Constants.pi/180;
   // Check if longitude is valid
   assert(abs(lon) < 2*Modelica.Constants.pi,
       "Wrong value for longitude. Received lon = " +
       String(lon) + " (= " + String(lon*180/Modelica.Constants.pi) + " degrees).");

end getLongitudeTMY3;

Buildings.BoundaryConditions.WeatherData.BaseClasses.getTimeZoneTMY3

Information

Inputs

Type	Name	Default	Description
String	filNam		Name of weather data file

Outputs

Type	Name	Description
Time	timZon	Time zone from the weather file [s]

Modelica definition

function getTimeZoneTMY3 
  "Gets the time zone from a TMY3 weather data file"
 input String filNam "Name of weather data file";
 output Modelica.SIunits.Time timZon "Time zone from the weather file";
protected 
 Integer nexInd "Next index, used for error handling";
 String element "String representation of the returned element";
algorithm 
  element :=
    Buildings.BoundaryConditions.WeatherData.BaseClasses.getHeaderElementTMY3(
      filNam=filNam,
      start="#LOCATION",
      name=  "longitude",
      position=9);
   (nexInd, timZon) :=Modelica.Utilities.Strings.Advanced.scanReal(
    string=element,
    startIndex=1,
    unsigned=false);
   assert(nexInd > 1, "Error when converting the time zone '" +
                      element + "' from a String to a Real.");
   timZon :=timZon*3600;
   // Check if time zone is valid
   assert(abs(timZon) < 24*3600,
       "Wrong value for time zone. Received timZon = " +
       String(timZon) + " (= " + String(timZon/3600) + " hours).");

end getTimeZoneTMY3;