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casellacasella
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Merge pull request #8 from antoniofroio/fixes
Added model Gas.Utilities.ClosedSystemInit
2 parents 65c8a5c + 04289e0 commit a654e28

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‎ThermoPower/Gas.mo‎

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@@ -2744,6 +2744,85 @@ The packages Medium are redeclared and a mass balance determines the composition
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</html>"));
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end FanMech;
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package Utility "Utility models"
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model ClosedSystemInit
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"Component for the steady-state initialization of closed systems"
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replaceable package Medium = Modelica.Media.Interfaces.PartialMedium
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"Medium model"
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annotation(choicesAllMatching = true);
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parameter Medium.AbsolutePressure pstart "Start value of pressure";
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parameter Boolean initEquationFromInput = false
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"Get initial condition residual from input connector"
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annotation(Dialog(group="External inputs"), choices(checkBox=true));
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parameter Boolean useHomotopy
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"Use homotopy for residual-based initialization";
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final parameter Medium.MassFlowRate w_b(fixed = false, start = 0)
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"Initial balance flow rate eventually equal to zero";
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outer ThermoPower.System system "System wide properties";
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FlangeB flange(redeclare package Medium = Medium, m_flow(min = 0))
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annotation (Placement(transformation(extent={{-20,-100},{20,-60}},
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rotation=0),
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iconTransformation(extent={{-20,-100},{20,-60}})));
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Modelica.Blocks.Interfaces.RealInput initEquationResidual if initEquationFromInput
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"Residual of initial equation" annotation (Placement(transformation(extent={
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{-60,0},{-20,40}}), iconTransformation(extent={{-60,-10},{-40,10}})));
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protected
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Modelica.Blocks.Interfaces.RealInput initEquationResidual_int
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"Hidden internal connector for conditional connection";
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equation
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0 = flange.m_flow + w_b "Mass balance";
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flange.h_outflow = Medium.h_default
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"Unused value as there is no flow out of the flange";
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flange.Xi_outflow = Medium.X_default[1:Medium.nXi]
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"Unused value as there is no flow out of the flange";
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connect(initEquationResidual, initEquationResidual_int)
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"Connects conditional input to hidden connector";
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if not initEquationFromInput then
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initEquationResidual_int = 0 "Not used";
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end if;
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initial equation
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if initEquationFromInput then
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if useHomotopy then
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homotopy(initEquationResidual_int, (flange.p - pstart)/pstart) = 0
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"Set initial value of residual to zero, simplified equation sets start value of pressure";
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else
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initEquationResidual_int = 0 "Set initial value of residual to zero";
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end if;
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else
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flange.p = pstart "Set initial value of pressure";
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end if;
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annotation (Icon(coordinateSystem(preserveAspectRatio=false), graphics={
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Line(
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points={{0,0},{0,-60}},
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color={159,159,223},
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thickness=0.5),
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Ellipse(
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extent={{-40,40},{40,-40}},
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lineColor={159,159,223},
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fillColor={159,159,223},
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fillPattern=FillPattern.Solid),
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Text(
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extent={{-32,24},{30,-24}},
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lineColor={255,255,255},
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lineThickness=0.5,
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fillColor={0,0,255},
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fillPattern=FillPattern.Solid,
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textString="Init")}), Diagram(
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coordinateSystem(preserveAspectRatio=false)),
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Documentation(info="<html>
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<p>This component can be used for the steady-state initialization of closed-system where all components have steady-state initial conditions. Without this component such systems would give rise to undetermined initial conditions, i.e., the amount of fluid and the initial pressures in the system would be unspecified.</p>
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<p>Connect the component to one point of the system. If <code>initEquationFromInput = false</code>, the system is initialized with pressure equal to <code>pstart</code> at the connection point.</p>
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<p>It is possible to use a generic initial equation instead of <code>p = pstart</code>, e.g., to set the initial charge of a refrigeration circuit, by setting <code>initEquationFromInput = true</code> and connecting to the input the output of a <a href=\"Modelica://Modelica.Blocks.Sources.RealExpression\">Modelica.Blocks.Sources.RealExpression</a> component, containing the residual of the initial equation. In this case, if <code>useHomotopy = true</code>, the simplified initial equation is <code>(p - pstart)/pstart = 0</code>. To ensure a smooth homotopy transformation, it is recommended to write the residual in normalized form, i.e., with values have the order of magnitude of one, as for the simplified equation.</p>
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</html>"));
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end ClosedSystemInit;
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end Utility;
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package BaseClasses
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extends Modelica.Icons.BasesPackage;
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partial model Flow1DBase

‎ThermoPower/Water.mo‎

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@@ -1374,7 +1374,7 @@ outlet is ignored; use <t>Pump</t> models if this has to be taken into account c
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end if;
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annotation (
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Diagram(graphics),
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Icon(graphics={Text(extent={{-100,-40},{100,-80}}, textString="%name")}),
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Icon(graphics={Text(extent={{-100,-60},{100,-100}},textString="%name")}),
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Documentation(info="<HTML>
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<p>This model describes the flow of water or steam in a rigid tube. The basic modelling assumptions are:
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<ul><li>The fluid state is always one-phase (i.e. subcooled liquid or superheated steam).
@@ -1463,7 +1463,7 @@ outlet is ignored; use <t>Pump</t> models if this has to be taken into account c
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connect(wall2,heatTransfer2.wall);
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annotation (Diagram(coordinateSystem(preserveAspectRatio=false, extent={{-100,
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-100},{100,100}}), graphics), Icon(coordinateSystem(
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preserveAspectRatio=false, extent={{-100,-100},{100,100}}), graphics));
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preserveAspectRatio=false, extent={{-100,-100},{100,100}})));
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end Flow1DFV2w;
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model Flow1DFV2ph
@@ -1786,7 +1786,7 @@ outlet is ignored; use <t>Pump</t> models if this has to be taken into account c
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annotation (
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Diagram(graphics),
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Icon(graphics={Text(extent={{-100,-40},{100,-80}}, textString="%name")}),
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Icon(graphics={Text(extent={{-100,-60},{100,-100}},textString="%name")}),
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Documentation(info="<HTML>
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<p>This model describes the flow of water or steam in a rigid tube. The basic modelling assumptions are:
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<ul><li>The fluid state is either one-phase, or a two-phase mixture.
@@ -2289,7 +2289,7 @@ enthalpy between the nodes; this requires the availability of the time derivativ
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end if;
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annotation (
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Diagram(graphics),
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Icon(graphics={Text(extent={{-100,-40},{100,-80}}, textString="%name")}),
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Icon(graphics={Text(extent={{-100,-60},{100,-100}},textString="%name")}),
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Documentation(info="<HTML>
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<p>This model describes the flow of water or steam in a rigid tube. The basic modelling assumptions are:
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<ul><li>The fluid state is always one-phase (i.e. subcooled liquid or superheated steam).

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