WOLFRAM SYSTEM MODELER
Version_2_2_2Version 2.2.2 (Aug. 31, 2007) 
SystemModel["Modelica.UsersGuide.ReleaseNotes.Version_2_2_2"]
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:
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 DifferencesModelica221222.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  6pulse rectifier with 1 transformer 
Rectifier12pulse  12pulse rectifier with 2 transformers 
AIMC_Steinmetz  Asynchronous induction machine squirrel cage with Steinmetz connection 
Electrical.Machines.BasicMachines.Components.  
BasicAIM  Partial model for asynchronous induction machine 
BasicSM  Partial model for synchronous induction 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 threephase transformer 
PartialCore  Partial model of transformer core with 3 windings 
IdealCore  Ideal transformer with 3 windings 
Electrical.Machines.BasicMachines.  
Transformers  SubLibrary 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 pnorm 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 zerodivision 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 sublibrary 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 MultiPhase 
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 ifconditions 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 3Delements 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 3Delements, 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 nonstandard Modelica function "constrain()" by standard Modelica components. As a result, the nonstandard 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 nonlinear equation system of a kinematic loop is formulated in a better way (the range where the desired result is a unique solution of the nonlinear system of equations becomes much larger). 
Mechanics.MultiBody.  
Visualizers.  Removed (misleading) annotation "structurallyIncomplete" in the models of this sublibrary 
Mechanics.Rotational.  
Examples  For all models in this sublibrary:

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 1sum(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):

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:

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.MultiPhase.Basic.  
Conductor  Changed wrong type of parameter G from SIunits.Resistance to SIunits.Conductance. 
Electrical.MultiPhase.Interfaces.  
Plug 
Made used "pin" connectors nongraphical (otherwise, there are difficulties to connect to Plug). 
Electrical.MultiPhase.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 nonflow 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". 