Changed models to make u instead of U a state

Also, set nominal attribute for Medium.T as this is a state if mSenFac > 1. For #1412

IBPSA/Fluid/Interfaces/ConservationEquation.mo

@@ -76,29 +76,23 @@ model ConservationEquation "Lumped volume with mass and energy balance"
 
   // Set nominal attributes where literal values can be used.
   Medium.BaseProperties medium(
+    preferredMediumStates = energyDynamics <> Modelica.Fluid.Types.Dynamics.SteadyState,
     p(start=p_start),
     h(start=hStart),
-    u(nominal=1E4,
-      stateSelect=StateSelect.prefer),
     T(start=T_start),
-    Xi(
-      start=X_start[1:Medium.nXi],
-      nominal=Medium.X_default[1:Medium.nXi],
-      stateSelect=StateSelect.prefer),
+    Xi(start=X_start[1:Medium.nXi]),
     X(start=X_start),
-    d(start=rho_start,
-      stateSelect=if massDynamics == Modelica.Fluid.Types.Dynamics.SteadyState
-      then StateSelect.default else StateSelect.prefer)) "Medium properties";
+    d(start=rho_start)) "Medium properties";
 
   Modelica.SIunits.Energy U(start=fluidVolume*rho_start*
     Medium.specificInternalEnergy(Medium.setState_pTX(
      T=T_start,
      p=p_start,
      X=X_start[1:Medium.nXi])) +
-    (T_start - Medium.reference_T)*CSen,
-    nominal = 1E5) "Internal energy of fluid";
+    (T_start - Medium.reference_T)*CSen) "Internal energy of fluid";
 
   Modelica.SIunits.Mass m(
+    min=Modelica.Constants.eps,
     start=fluidVolume*rho_start)
     "Mass of fluid";
 
@@ -125,11 +119,8 @@ model ConservationEquation "Lumped volume with mass and energy balance"
   parameter Modelica.SIunits.Volume fluidVolume "Volume";
   final parameter Modelica.SIunits.HeatCapacity CSen=
     (mSenFac - 1)*rho_default*cp_default*fluidVolume
-    "Aditional heat capacity for implementing mFactor";
+    "Additional heat capacity for implementing mFactor";
 protected
-  Medium.EnthalpyFlowRate ports_H_flow[nPorts];
-  Modelica.SIunits.MassFlowRate ports_mXi_flow[nPorts,Medium.nXi];
-  Medium.ExtraPropertyFlowRate ports_mC_flow[nPorts,Medium.nC];
   parameter Modelica.SIunits.SpecificHeatCapacity cp_default=
   Medium.specificHeatCapacityCp(state=state_default)
     "Heat capacity, to compute additional dry mass";
@@ -165,6 +156,14 @@ protected
   constant Boolean _simplify_mWat_flow = simplify_mWat_flow and Medium.nX > 1
    "If true, then port_a.m_flow + port_b.m_flow = 0 even if mWat_flow is non-zero, and equations are simplified";
 
+  // Quantities exchanged through the fluid ports
+  Medium.EnthalpyFlowRate ports_H_flow[nPorts]
+    "Enthalpy flow rates at the ports";
+  Modelica.SIunits.MassFlowRate ports_mXi_flow[nPorts, Medium.nXi]
+    "Mass fraction flow rates at the ports";
+  Medium.ExtraPropertyFlowRate ports_mC_flow[nPorts, Medium.nC]
+    "Trace substance flow rates at the ports";
+
   // Conditional connectors
   Modelica.Blocks.Interfaces.RealInput mWat_flow_internal(unit="kg/s")
     "Needed to connect to conditional connector";

IBPSA/Media/Air.mo

@@ -55,17 +55,20 @@ package Air
 
   InputAbsolutePressure p "Absolute pressure of medium";
   InputMassFraction[1] Xi(
-    start=reference_X[1:1],
+    start=X_default[1:1],
+    nominal={0.01},
     each stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)
     "Structurally independent mass fractions";
   InputSpecificEnthalpy h "Specific enthalpy of medium";
   Modelica.Media.Interfaces.Types.Density d "Density of medium";
   Modelica.Media.Interfaces.Types.Temperature T(
-   stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)
+   nominal=100)
    "Temperature of medium";
   Modelica.Media.Interfaces.Types.MassFraction[2] X(start=reference_X)
     "Mass fractions (= (component mass)/total mass  m_i/m)";
-  Modelica.Media.Interfaces.Types.SpecificInternalEnergy u
+  Modelica.Media.Interfaces.Types.SpecificInternalEnergy u(
+   nominal=1E4,
+   stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)
     "Specific internal energy of medium";
   Modelica.Media.Interfaces.Types.SpecificHeatCapacity R
     "Gas constant (of mixture if applicable)";

IBPSA/Media/Antifreeze/PropyleneGlycolWater.mo

@@ -31,15 +31,15 @@ package PropyleneGlycolWater
     "Mass fraction of propylene glycol in water";
 
   redeclare model BaseProperties "Base properties"
-    Temperature T(stateSelect=
-      if preferredMediumStates then StateSelect.prefer else StateSelect.default)
-      "Temperature of medium";
+    Temperature T "Temperature of medium";
 
     InputAbsolutePressure p "Absolute pressure of medium";
     InputMassFraction[nXi] Xi=fill(0, 0)
       "Structurally independent mass fractions";
     InputSpecificEnthalpy h "Specific enthalpy of medium";
-    Modelica.SIunits.SpecificInternalEnergy u
+    Modelica.SIunits.SpecificInternalEnergy u(
+     nominal=1E4,
+     stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)
       "Specific internal energy of medium";
     Modelica.SIunits.Density d=d_const "Density of medium";
     Modelica.SIunits.MassFraction[nX] X={1}

IBPSA/Media/Specialized/Air/PerfectGas.mo

@@ -27,8 +27,12 @@ package PerfectGas "Model for air as a perfect gas"
   end ThermodynamicState;
 
   redeclare replaceable model extends BaseProperties(
-    p(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default),
-    Xi(each stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default),
+    u(nominal=1E4,
+      stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default),
+    d(stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default),
+    Xi(
+      nominal={0.01},
+      each stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default),
     final standardOrderComponents=true)
 
     /* p, T, X = X[Water] are used as preferred states, since only then all
@@ -61,7 +65,7 @@ as required from medium model \"" + mediumName + "\".");
     R = dryair.R*(1 - X_steam) + steam.R*X_steam;
     //
     u = h - R*T;
-    p = d*R*T;
+    d = p/(R*T);
     /* Note, u and d are computed under the assumption that the volume of the liquid
          water is negligible with respect to the volume of air and of steam
       */

IBPSA/Media/Specialized/Water/TemperatureDependentDensity.mo

@@ -20,17 +20,18 @@ package TemperatureDependentDensity
     each casRegistryNumber="7732-18-5",
     each iupacName="oxidane",
     each molarMass=MM_const);
-
   redeclare record extends ThermodynamicState "Thermodynamic state variables"
     Temperature T(start=T_default) "Temperature of medium";
     AbsolutePressure p(start=p_default) "Pressure of medium";
   end ThermodynamicState;
-
   constant Modelica.SIunits.SpecificHeatCapacity cp_const = 4184
     "Specific heat capacity at constant pressure";
 
   redeclare model extends BaseProperties(
-     preferredMediumStates=true) "Base properties"
+    u(nominal=1E4,
+      stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default))
+     "Base properties"
+
   equation
     h = (T - reference_T)*cp_const;
     u = h-reference_p/d;
@@ -662,7 +663,6 @@ First implementation.
 </ul>
 </html>"));
 end setState_psX;
-
 //////////////////////////////////////////////////////////////////////
 // Protected classes.
 // These classes are only of use within this medium model.
@@ -786,8 +786,7 @@ but converted from Celsius to Kelvin.
 </ul>
 </html>"));
 end kinematicViscosity;
-
-annotation(preferredView="info", Documentation(info="<html>
+annotation(Documentation(info="<html>
 <p>
 This medium package models liquid water.
 </p>

IBPSA/Media/Water.mo

@@ -19,14 +19,15 @@ package Water "Package with model for liquid water with constant density"
     final parameter Boolean standardOrderComponents=true
       "If true, and reducedX = true, the last element of X will be computed from the other ones";
     Modelica.SIunits.Density d=d_const "Density of medium";
-    Temperature T(stateSelect=
-      if preferredMediumStates then StateSelect.prefer else StateSelect.default)
+    Temperature T
       "Temperature of medium";
     InputAbsolutePressure p "Absolute pressure of medium";
     InputMassFraction[nXi] Xi=fill(0, 0)
       "Structurally independent mass fractions";
     InputSpecificEnthalpy h "Specific enthalpy of medium";
-    Modelica.SIunits.SpecificInternalEnergy u
+    Modelica.SIunits.SpecificInternalEnergy u(
+      nominal=1E4,
+      stateSelect=if preferredMediumStates then StateSelect.prefer else StateSelect.default)
       "Specific internal energy of medium";
 
     Modelica.SIunits.MassFraction[nX] X={1}

IBPSA/Resources/Scripts/Dymola/Fluid/Interfaces/Examples/Humidifier_u.mos

@@ -1,4 +1,4 @@
-simulateModel("IBPSA.Fluid.Interfaces.Examples.Humidifier_u", method="Radau", stopTime=3600, tolerance=1e-6, resultFile="InterfacesHumidifier_u");
+simulateModel("IBPSA.Fluid.Interfaces.Examples.Humidifier_u", method="Cvode", stopTime=3600, tolerance=1e-6, resultFile="InterfacesHumidifier_u");
 createPlot(id=1, position={15, 10, 413, 444}, y={"hea1.sta_a.T", "hea1.sta_b.T", "hea2.sta_a.T", "hea2.sta_b.T"}, range={0.0, 4000.0, 15.0, 21.0}, grid=true, colors={{28,108,200}, {238,46,47}, {0,140,72}, {217,67,180}});
 createPlot(id=1, position={15, 10, 413, 220}, y={"hea3.sta_a.T", "hea3.sta_b.T", "hea4.sta_a.T", "hea4.sta_b.T", "mix1.T"}, range={0.0, 4000.0, 15.0, 21.0}, grid=true, subPlot=2, colors={{28,108,200}, {238,46,47}, {0,140,72}, {217,67,180}, {0,0,0}});
 createPlot(id=3, position={435, 8, 400, 447}, y={"hea1.m_flow", "hea2.m_flow"}, range={0.0, 4000.0, -0.6000000000000001, 0.8}, grid=true, colors={{28,108,200}, {238,46,47}});