blockCFDExchange

Block that exchanges data with the CFD code

Extends from Modelica.Blocks.Interfaces.DiscreteBlock (Base class of discrete control blocks).

Information

This block samples interface variables and exchanges data with the CFD code.

For a documentation of the exchange parameters and variables, see Buildings.ThermalZones.Detailed.UsersGuide.CFD.

Type	Name	Default	Description
SI.Time	samplePeriod (from DiscreteBlock)		Sample period of component
SI.Time	startTime (from DiscreteBlock)	0	First sample time instant
String	cfdFilNam		CFD input file name
Boolean	activateInterface	true	Set to false to deactivate interface and use instead yFixed as output
Integer	nXi		Number of independent species concentration of the inflowing medium
Integer	nC		Number of trace substances of the inflowing medium
Integer	nWri		Number of values to write to the CFD simulation
Integer	nRea		Number of double values to be read from the CFD simulation
Integer[nWri]	flaWri	ones(nWri)	Flag for double values (0: use current value, 1: use average over interval, 2: use integral over interval)
Real[nRea]	yFixed		Fixed output, used if activateInterface=false
Integer	nSur		Number of surfaces
Integer	nConExtWin		number of exterior construction with window
CFDSurfaceIdentifier[nSur]	surIde		Surface identifiers
Boolean	haveShade		Set to true if at least one window in the room has a shade
Boolean	haveSensor		Flag, true if the model has at least one sensor
String[:]	sensorName		Names of sensors as declared in the CFD input file
String[:]	portName		Names of fluid ports as declared in the CFD input file
Boolean	verbose	false	Set to true for verbose output
Modelica.Units.SI.Density	rho_start		Density at initial state

Type	Name	Default	Description
Modelica.Blocks.Interfaces.RealInput[nWri]	u		Inputs to CFD
Modelica.Blocks.Interfaces.RealOutput[nRea]	y		Outputs received from CFD

Type	Name	Default	Description
CFDThread	CFDThre	CFDThread()	Allocate memory for cosimulation variables via constructor and send stop command to FFD via destructor
Real[nWri]	uInt		Value of integral
Real[nWri]	uIntPre		Value of integral at previous sampling instance
Real[nWri]	uWri		Value to be sent to the CFD interface

Name	Description
sendParametersprotected
exchangeprotected
returnNonUniqueStringsprotected
assertStringsAreUniqueprotected

October 2, 2025, by Michael Wetter:
Declared functions as impure.
January 12, 2019, by Michael Wetter:
Removed Evaluate statement as the model is used with fixed=false which causes a warning in JModelica.
July 27, 2018, by Wei Tian and Xu Han:
To fix the issue FFD fails in JModelica tests due to unsupported OS #612 at issue 612. November 17, 2016, by Michael Wetter:
Removed public parameter uStart, which is not needed and refactored model.
This is for issue 579.
April 21, 2016, by Michael Wetter:
Movded call to Buildings.BoundaryConditions.WeatherData.BaseClasses.getAbsolutePath from this model to Buildings.ThermalZones.Detailed.CFD. This is for Buildings, #506.
September 28, 2015, by Michael Wetter:
Provided start value for all variables to avoid warning in the pedantic Modelica check in Dymola 2016 about unspecified initial conditions. This closes issue 459.
June 4, 2015, by Michael Wetter:
Set start and fixed attributes in u[nWri](start=_uStart, each fixed=true) to avoid a warning in Dymola 2016 about unspecified initial conditions. This closes issue 422.
February 6, 2015, by Michael Wetter:
Changed initial algorithm to initial equation.
January 24, 2014, by Wangda Zuo:
Enabled the transfer of Xi and X to CFD.
July 19, 2013, by Michael Wetter:
First implementation.