This information is part of the Modelica Standard Library maintained by the Modelica Association.

Version 2.2.2 is backward compatible to version 2.2.1 and 2.2 with the following exceptions:

• Removal of package Modelica.Media.Interfaces.PartialTwoPhaseMediumWithCache (this was not yet utilized).
• Removal of the media packages in Modelica.Media.IdealGases.SingleGases that are not type compatible to Modelica.Media.Interfaces.PartialMedium, because a FluidConstants record definition is missing, for details, see Modelica.Media.IdealGases (this is seen as a bug fix).

An overview of the differences between version 2.2.2 and the previous version 2.2.1 is given below. The exact differences (but without differences in the documentation) are available in Differences-Modelica-221-222.html. This comparison file was generated automatically with Dymola's ModelManagement.compare function.

In this version, no new libraries have been added. The documentation of the whole library was improved.

The following new components have been added to existing libraries:

Blocks.Logical.
TerminateSimulation	Terminate a simulation by a given condition.
Blocks.Routing.
RealPassThrough IntegerPassThrough BooleanPassThrough	Pass a signal from input to output (useful in combination with a bus due to restrictions of expandable connectors).
Blocks.Sources.
KinematicPTP2	Directly gives q,qd,qdd as output (and not just qdd as KinematicPTP).
Electrical.Machines.Examples.
TransformerTestbench	Transformer Testbench
Rectifier6pulse	6-pulse rectifier with 1 transformer
Rectifier12pulse	12-pulse rectifier with 2 transformers
AIMC_Steinmetz	Induction machine squirrel cage with Steinmetz connection
Electrical.Machines.BasicMachines.Components.
BasicAIM	Partial model for induction machine
BasicSM	Partial model for synchronous machine
PartialAirGap	Partial air gap model
BasicDCMachine	Partial model for DC machine
PartialAirGapDC	Partial air gap model of a DC machine
BasicTransformer	Partial model of three-phase transformer
PartialCore	Partial model of transformer core with 3 windings
IdealCore	Ideal transformer with 3 windings
Electrical.Machines.BasicMachines.
Transformers	Sub-Library for technical 3phase transformers
Electrical.Machines.Interfaces.
Adapter	Adapter to model housing of electrical machine
Math.
Vectors	New library of functions operating on vectors
atan3	Four quadrant inverse tangent (select solution that is closest to given angle y0)
asinh	Inverse of sinh (area hyperbolic sine)
acosh	Inverse of cosh (area hyperbolic cosine)
Math.Vectors
isEqual	Determine if two Real vectors are numerically identical
norm	Return the p-norm of a vector
length	Return length of a vector (better as norm(), if further symbolic processing is performed)
normalize	Return normalized vector such that length = 1 and prevent zero-division for zero vector
reverse	Reverse vector elements (e.g., v[1] becomes last element)
sort	Sort elements of vector in ascending or descending order
Math.Matrices
solve2	Solve real system of linear equations A*X=B with a B matrix (Gaussian elimination with partial pivoting)
LU_solve2	Solve real system of linear equations P*L*U*X=B with a B matrix and an LU decomposition (from LU(..))
Mechanics.Rotational.
InitializeFlange	Initialize a flange according to given signals (useful if initialization signals are provided by a signal bus).
Media.Interfaces.PartialMedium.
density_pTX	Return density from p, T, and X or Xi
Media.Interfaces.PartialTwoPhaseMedium.
BaseProperties	Base properties (p, d, T, h, u, R, MM, x) of a two phase medium
molarMass	Return the molar mass of the medium
saturationPressure_sat	Return saturation pressure
saturationTemperature_sat	Return saturation temperature
saturationTemperature_derp_sat	Return derivative of saturation temperature w.r.t. pressure
setState_px	Return thermodynamic state from pressure and vapour quality
setState_Tx	Return thermodynamic state from temperature and vapour quality
vapourQuality	Return vapour quality
Media.Interfaces.
PartialLinearFluid	Generic pure liquid model with constant cp, compressibility and thermal expansion coefficients
Media.Air.MoistAir.
massFraction_pTphi	Return the steam mass fraction from relative humidity and T
saturationTemperature	Return saturation temperature from (partial) pressure via numerical inversion of function saturationPressure
enthalpyOfWater	Return specific enthalpy of water (solid/liquid) near atmospheric pressure from temperature
enthalpyOfWater_der	Return derivative of enthalpyOfWater()" function
PsychrometricData	Model to generate plot data for psychrometric chart
Media.CompressibleLiquids. New sub-library for simple compressible liquid models
LinearColdWater	Cold water model with linear compressibility
LinearWater_pT_Ambient	Liquid, linear compressibility water model at 1.01325 bar and 25 degree Celsius
SIunits.
TemperatureDifference	Type for temperature difference

The following existing components have been improved:

Blocks.Examples.
BusUsage	Example changed from the "old" to the "new" bus concept with expandable connectors.
Blocks.Discrete.
ZeroOrderHold	Sample output ySample moved from "protected" to "public" section with new attributes (start=0, fixed=true).
TransferFunction	Discrete state x with new attributes (each start=0, each fixed=0).
Electrical.
Analog Polyphase	Improved some icons.
Electrical.Digital.Interfaces.
MISO	Removed "algorithm" from this partial block.
Electrical.Digital.Delay.
DelayParams	Removed "algorithm" from this partial block.
Electrical.Digital.Delay.
DelayParams	Removed "algorithm" from this partial block.
TransportDelay	If delay time is zero, an infinitely small delay is introduced via pre(x) (previously "x" was used).
Electrical.Digital.Sources.
Clock Step	Changed if-conditions from "xxx < time" to "time >= xxx" (according to the Modelica specification, in the second case a time event should be triggered, i.e., this change leads potentially to a faster simulation).
Electrical.Digital.Converters.
BooleanToLogic LogicToBoolean RealToLogic LogicToReal	Changed from "algorithm" to "equation" section to allow better symbolic preprocessing
Electrical.
Machines	Slightly improved documentation, typos in documentation corrected
Electrical.Machines.Examples.
AIMS_start	Changed QuadraticLoadTorque1(TorqueDirection=true) to QuadraticLoadTorque1(TorqueDirection=false) since more realistic
Electrical.Machines.Interfaces.
PartialBasicMachine	Introduced support flange to model the reaction torque to the housing
Electrical.Machines.Sensors.
Rotorangle	Introduced support flange to model the reaction torque to the housing
Mechanics.MultiBody.Examples.Elementary.
PointMassesWithGravity	Added two point masses connected by a line force to demonstrate additionally how this works. Connections of point masses with 3D-elements are demonstrated in the new example PointMassesWithGravity (there is the difficulty that the orientation is not defined in a PointMass object and therefore some special handling is needed in case of a connection with 3D-elements, where the orientation of the point mass is not determined by these elements.
Mechanics.MultiBody.Examples.Systems.
RobotR3	Changed from the "old" to the "new" bus concept with expandable connectors. Replaced the non-standard Modelica function "constrain()" by standard Modelica components. As a result, the non-standard function constrain() is no longer used in the Modelica Standard Library.
Mechanics.MultiBody.Frames.Orientation.
equalityConstraint	Use a better residual for the equalityConstraint function. As a result, the non-linear equation system of a kinematic loop is formulated in a better way (the range where the desired result is a unique solution of the non-linear system of equations becomes much larger).
Mechanics.MultiBody.
Visualizers.	Removed (misleading) annotation "structurallyIncomplete" in the models of this sub-library
Mechanics.Rotational.
Examples	For all models in this sub-library: Included a housing object in all examples to compute all support torques. Replaced initialization by modifiers via the initialization menu parameters of Inertia components. Removed "encapsulated" and unnecessary "import". Included "StopTime" in the annotations.
Mechanics.Rotational.Interfaces.
FrictionBase	Introduced "fixed=true" for Boolean variables startForward, startBackward, mode.
Mechanics.Translational.Interfaces.
FrictionBase	Introduced "fixed=true" for Boolean variables startForward, startBackward, mode.
Media.UsersGuide.MediumUsage.
TwoPhase	Improved documentation and demonstrating the newly introduced functions
Media.Examples.
WaterIF97	Provided (missing) units for variables V, dV, H_flow_ext, m, U.
Media.Interfaces.
PartialMedium	Final modifiers are removed from nX and nXi, to allow customized medium models such as mixtures of refrigerants with oil, etc.
PartialCondensingGases	Included attributes "min=1, max=2" for input argument FixedPhase for functions setDewState and setBubbleState (in order to guarantee that input arguments are correct).
Media.Interfaces.PartialMedium.
BaseProperties	New Boolean parameter "standardOrderComponents". If true, last element vector X is computed from 1-sum(Xi) (= default) otherwise, no equation is provided for it in PartialMedium.
IsentropicExponent	"max" value changed from 1.7 to 500000
setState_pTX setState_phX setState_psX setState_dTX specificEnthalpy_pTX temperature_phX density_phX temperature_psX density_psX specificEnthalpy_psX	Introduced default value "reference_X" for input argument "X".
Media.Interfaces.PartialSimpleMedium.
setState_pTX setState_phX setState_psX setState_dTX	Introduced default value "reference_X" for input argument "X".
Media.Interfaces.PartialSimpleIdealGasMedium.
setState_pTX setState_phX setState_psX setState_dTX	Introduced default value "reference_X" for input argument "X".
Media.Air.MoistAir.
setState_pTX setState_phX setState_dTX	Introduced default value "reference_X" for input argument "X".
Media.IdealGases.Common.SingleGasNasa.
setState_pTX setState_phX setState_psX setState_dTX	Introduced default value "reference_X" for input argument "X".
Media.IdealGases.Common.MixtureGasNasa.
setState_pTX setState_phX setState_psX setState_dTX h_TX	Introduced default value "reference_X" for input argument "X".
Media.Common.
IF97PhaseBoundaryProperties gibbsToBridgmansTables	Introduced unit for variables vt, vp.
SaturationProperties	Introduced unit for variable dpT.
BridgmansTables	Introduced unit for dfs, dgs.
Media.Common.ThermoFluidSpecial.
gibbsToProps_ph gibbsToProps_ph gibbsToBoundaryProps gibbsToProps_dT gibbsToProps_pT	Introduced unit for variables vt, vp.
TwoPhaseToProps_ph	Introduced unit for variables dht, dhd, detph.
Media.
MoistAir	Documentation of moist air model significantly improved.
Media.MoistAir.
enthalpyOfVaporization	Replaced by linear correlation since simpler and more accurate in the entire region.
Media.Water.IF97_Utilities.BaseIF97.Regions.
drhovl_dp	Introduced unit for variable dd_dp.
Thermal.
FluidHeatFlow	Introduced new parameter tapT (0..1) to define the temperature of the HeatPort as linear combination of the flowPort_a (tapT=0) and flowPort_b (tapT=1) temperatures.

The following critical errors have been fixed (i.e., errors that can lead to wrong simulation results):

Electrical.Machines.BasicMachines.Components.
ElectricalExcitation	Excitation voltage ve is calculated as "spacePhasor_r.v_[1]*TurnsRatio*3/2" instead of "spacePhasor_r.v_[1]*TurnsRatio
Mechanics.MultiBody.Parts.
FixedRotation	Bug corrected that the torque balance was wrong in the following cases (since vector r was not transformed from frame_a to frame_b; note this special case occurs very seldom in practice): frame_b is in the spanning tree closer to the root (usually this is frame_a). vector r from frame_a to frame_b is not zero.
PointMass	If a PointMass model is connected so that no equations are present to compute its orientation object, the orientation was arbitrarily set to a unit rotation. In some cases this can lead to a wrong overall model, depending on how the PointMass model is used. For this reason, such cases lead now to an error (via an assert(..)) with an explanation how to fix this.
Media.Interfaces.PartialPureSubstance.
pressure_dT specificEnthalpy_dT	Changed wrong call from "setState_pTX" to "setState_dTX"
Media.Interfaces.PartialTwoPhaseMedium.
pressure_dT specificEnthalpy_dT	Changed wrong call from "setState_pTX" to "setState_dTX"
Media.Common.ThermoFluidSpecial.
gibbsToProps_dT helmholtzToProps_ph helmholtzToProps_pT helmholtzToProps_dT	Bugs in equations corrected
Media.Common.
helmholtzToBridgmansTables helmholtzToExtraDerivs	Bugs in equations corrected
Media.IdealGases.Common.SingleGasNasa.
density_derp_T	Bug in equation of partial derivative corrected
Media.Water.IF97_Utilities.
BaseIF97.Inverses.dtofps3 isentropicExponent_props_ph isentropicExponent_props_pT isentropicExponent_props_dT	Bugs in equations corrected
Media.Air.MoistAir.
h_pTX	Bug in setState_phX due to wrong vector size in h_pTX corrected. Furthermore, syntactical errors corrected: In function massFractionpTphi an equation sign is used in an algorithm. Two consecutive semicolons removed
Media.Water.
waterConstants	Bug in equation of criticalMolarVolume corrected.
Media.Water.IF97_Utilities.BaseIF97.Regions.
region_ph region_ps	Bug in region determination corrected.
boilingcurve_p dewcurve_p	Bug in equation of plim corrected.

The following uncritical errors have been fixed (i.e., errors that do not lead to wrong simulation results, but, e.g., units are wrong or errors in documentation):

Blocks.
Examples	Corrected typos in description texts of bus example models.
Blocks.Continuous.
LimIntegrator	removed incorrect smooth(0,..) because expression might be discontinuous.
Blocks.Math.UnitConversions.
block_To_kWh block_From_kWh	Corrected unit from "kWh" to (syntactically correct) "kW.h".
Electrical.Analog.Examples.
HeatingNPN_OrGate	Included start values, so that initialization is successful
Electrical.Analog.Lines.
OLine	Corrected unit from "Siemens/m" to "S/m".
TLine2	Changed wrong type of parameter NL (normalized length) from SIunits.Length to Real.
Electrical.Digital.Delay.
TransportDelay	Syntax error corrected (":=" in equation section is converted by Dymola silently to "=").
Electrical.Digital
Converters	Syntax error corrected (":=" in equation section is converted by Dymola silently to "=").
Electrical.Polyphase.Basic.
Conductor	Changed wrong type of parameter G from SIunits.Resistance to SIunits.Conductance.
Electrical.Polyphase.Interfaces.
Plug	Made used "pin" connectors non-graphical (otherwise, there are difficulties to connect to Plug).
Electrical.Polyphase.Sources.
SineCurrent	Changed wrong type of parameter offset from SIunits.Voltage to SIunits.Current.
Mechanics.MultiBody.Examples.Loops.
EngineV6	Corrected wrong crankAngleOffset of some cylinders and improved the example.
Mechanics.MultiBody.Examples.Loops.Utilities.
GasForce	Wrong units corrected: "SIunitsPosition x,y" to "Real x,y"; "SIunits.Pressure press" to "SIunits.Conversions.NonSIunits.Pressure_bar"
GasForce2	Wrong unit corrected: "SIunits.Position x" to "Real x".
EngineV6_analytic	Corrected wrong crankAngleOffset of some cylinders.
Mechanics.MultiBody.Interfaces.
PartialLineForce	Corrected wrong unit: "SIunits.Position eRod_a" to "Real eRod_a";
FlangeWithBearingAdaptor	If includeBearingConnector = false, connector "fr" + "ame" was not removed. As long as the connecting element to "frame" determines the non-flow variables, this is fine. In the corrected version, "frame" is conditionally removed in this case.
Mechanics.MultiBody.Forces.
ForceAndTorque	Corrected wrong unit: "SIunits.Force t_b_0" to "SIunits.Torque t_b_0".
LineForceWithTwoMasses	Corrected wrong unit: "SIunits.Position e_rel_0" to "Real e_rel_0".
Mechanics.MultiBody.Frames.
axisRotation	Corrected wrong unit: "SIunits.Angle der_angle" to "SIunits.AngularVelocity der_angle".
Mechanics.MultiBody.Joints.Assemblies.
JointUSP JointSSP	Corrected wrong unit: "SIunits.Position aux" to "Real"
Mechanics.MultiBody.Sensors.
AbsoluteSensor	Corrected wrong units: "SIunits.Acceleration angles" to "SIunits.Angle angles" and "SIunits.Velocity w_abs_0" to "SIunits.AngularVelocity w_abs_0"
RelativeSensor	Corrected wrong units: "SIunits.Acceleration angles" to "SIunits.Angle angles"
Distance	Corrected wrong units: "SIunits.Length L2" to "SIunits.Area L2" and SIunits.Length s_small2" to "SIunits.Area s_small2"
Mechanics.MultiBody.Visualizers.Advanced.
Shape	Changed "MultiBody.Types.Color color" to "Real color[3]", since "Types.Color" is "Integer color[3]" and there have been backward compatibility problems with models using "color" before it was changed to "Types.Color".
Mechanics.Rotational.Interfaces.
FrictionBase	Rewrote equations with new variables "unitAngularAcceleration" and "unitTorque" in order that the equations are correct with respect to units (previously, variable "s" can be both a torque and an angular acceleration and this lead to unit incompatibilities)
Mechanics.Rotational.
OneWayClutch LossyGear	Rewrote equations with new variables "unitAngularAcceleration" and "unitTorque" in order that the equations are correct with respect to units (previously, variable "s" can be both a torque and an angular acceleration and this lead to unit incompatibilities)
Mechanics.Translational.Interfaces.
FrictionBase	Rewrote equations with new variables "unitAngularAcceleration" and "unitTorque" in order that the equations are correct with respect to units (previously, variable "s" can be both a torque and an angular acceleration and this lead to unit incompatibilities)
Mechanics.Translational.
Speed	Corrected unit of v_ref from SIunits.Position to SIunits.Velocity
Media.Examples.Tests.Components.
PartialTestModel PartialTestModel2	Corrected unit of h_start from "SIunits.Density" to "SIunits.SpecificEnthalpy"
Media.Examples.SolveOneNonlinearEquation.
Inverse_sh_T InverseIncompressible_sh_T Inverse_sh_TX	Rewrote equations so that dimensional (unit) analysis is correct"
Media.Incompressible.Examples.
TestGlycol	Rewrote equations so that dimensional (unit) analysis is correct"
Media.Interfaces.PartialTwoPhaseMedium.
dBubbleDensity_dPressure dDewDensity_dPressure	Changed wrong type of ddldp from "DerDensityByEnthalpy" to "DerDensityByPressure".
Media.Common.ThermoFluidSpecial.
ThermoProperties	Changed wrong units: "SIunits.DerEnergyByPressure dupT" to "Real dupT" and "SIunits.DerEnergyByDensity dudT" to "Real dudT"
ThermoProperties_ph	Changed wrong unit from "SIunits.DerEnergyByPressure duph" to "Real duph"
ThermoProperties_pT	Changed wrong unit from "SIunits.DerEnergyByPressure dupT" to "Real dupT"
ThermoProperties_dT	Changed wrong unit from "SIunits.DerEnergyByDensity dudT" to "Real dudT"
Media.IdealGases.Common.SingleGasNasa.
cp_Tlow_der	Changed wrong unit from "SIunits.Temperature dT" to "Real dT".
Media.Water.IF97_Utilities.BaseIF97.Basic.
p1_hs h2ab_s p2a_hs p2b_hs p2c_hs h3ab_p T3a_ph T3b_ph v3a_ph v3b_ph T3a_ps T3b_ps v3a_ps v3b_ps	Changed wrong unit of variables h/hstar, s, sstar from "SIunits.Enthalpy" to "SIunits.SpecificEnthalpy", "SIunits.SpecificEntropy", "SIunits.SpecificEntropy
Media.Water.IF97_Utilities.BaseIF97.Transport.
cond_dTp	Changed wrong unit of TREL, rhoREL, lambdaREL from "SIunits.Temperature", "SIunit.Density", "SIunits.ThermalConductivity" to "Real".
Media.Water.IF97_Utilities.BaseIF97.Inverses.
tofps5 tofpst5	Changed wrong unit of pros from "SIunits.SpecificEnthalpy" to "SIunits.SpecificEntropy".
Media.Water.IF97_Utilities.
waterBaseProp_ph	Improved calculation at the limits of the validity.
Thermal.
FluidHeatFlow HeatTransfer	Corrected wrong unit "SIunits.Temperature" of difference temperature variables with "SIunits.TemperatureDifference".