root/branches/maintenance/2.2.2/Modelica/Thermal/HeatTransfer.mo

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1within Modelica.Thermal;
2package HeatTransfer
3  "Library of 1-dimensional heat transfer with lumped elements" 
4  import Modelica.SIunits.Conversions.*;
5  import SI = Modelica.SIunits;
6  import NonSI = Modelica.SIunits.Conversions.NonSIunits;
7  extends Modelica.Icons.Library2;
8 
9  annotation (version="1.1", versionDate="2005-06-13",
10    preferedView="info", Icon(
11      Polygon(points=[-54, -6; -61, -7; -75, -15; -79, -24; -80, -34; -78, -42;
12              -73, -49; -64, -51; -57, -51; -47, -50; -41, -43; -38, -35; -40,
13            -27; -40, -20; -42, -13; -47, -7; -54, -5; -54, -6], style(color=10,
14              fillColor=8)),
15      Polygon(points=[-75, -15; -79, -25; -80, -34; -78, -42; -72, -49; -64, -
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20            51, -13; 46, -7; 39, -5; 39, -6], style(color=9, fillColor=8)),
21      Polygon(points=[18, -15; 14, -25; 13, -34; 15, -42; 21, -49; 29, -51; 36,
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24      Polygon(points=[-9, -23; -9, -10; 18, -17; -9, -23], style(
25          color=42,
26          fillColor=42,
27          fillPattern=1)),
28      Line(points=[-41, -17; -9, -17], style(color=42, thickness=2)),
29      Line(points=[-17, -40; 15, -40], style(color=42, thickness=2)),
30      Polygon(points=[-17, -46; -17, -34; -40, -40; -17, -46], style(
31          color=42,
32          fillColor=42,
33          fillPattern=1))), Documentation(info="<HTML>
34<p>
35This package contains components to model <b>1-dimensional heat transfer</b>
36with lumped elements. This allows especially to model heat transfer in
37machines provided the parameters of the lumped elements, such as
38the heat capacity of a part, can be determined by measurements
39(due to the complex geometries and many materials used in machines,
40calculating the lumped element parameters from some basic analytic
41formulas is usually not possible).
42</p>
43<p>
44Example models how to use this library are given in subpackage <b>Examples</b>.<br>
45For a first simple example, see <b>Examples.TwoMasses</b> where two masses
46with different initial temperatures are getting in contact to each
47other and arriving after some time at a common temperature.<br>
48<b>Examples.ControlledTemperature</b> shows how to hold a temperature
49within desired limits by switching on and off an electric resistor.<br>
50A more realistic example is provided in <b>Examples.Motor</b> where the
51heating of an electrical motor is modelled, see the following screen shot
52of this example:
53</p>
54<img src=\"../Images/driveWithHeatTransfer.png\" ALT=\"driveWithHeatTransfer\">
55<p>
56The <b>filled</b> and <b>non-filled red squares</b> at the left and
57right side of a component represent <b>thermal ports</b> (connector HeatPort).
58Drawing a line between such squares means that they are thermally connected.
59The variables of a HeatPort connector are the temperature <b>T</b> at the port
60and the heat flow rate <b>Q_flow</b> flowing into the component (if Q_flow is positive,
61the heat flows into the element, otherwise it flows out of the element):
62</p>
63<pre>   Modelica.SIunits.Temperature  T  \"absolute temperature at port in Kelvin\";
64   Modelica.SIunits.HeatFlowRate Q_flow  \"flow rate at the port in Watt\";
65</pre>
66<p>
67Note, that all temperatures of this package, including initial conditions,
68are given in Kelvin. For convenience, in subpackages <b>HeatTransfer.Celsius</b>,
69 <b>HeatTransfer.Fahrenheit</b> and <b>HeatTransfer.Rankine</b> components are provided such that source and
70sensor information is available in degree Celsius, degree Fahrenheit, or degree Rankine,
71respectively. Additionally, in package <b>SIunits.Conversions</b> conversion
72functions between the units Kelvin and Celsius, Fahrenheit, Rankine are
73provided. These functions may be used in the following way:
74</p>
75<pre>  <b>import</b> SI=Modelica.SIunits;
76  <b>import</b> Modelica.SIunits.Conversions.*;
77     ...
78  <b>parameter</b> SI.Temperature T = from_degC(25);  // convert 25 degree Celsius to Kelvin
79</pre>
80
81<p>
82There are several other components available, such as AxialConduction (discretized PDE in
83axial direction), which have been temporarily removed from this library. The reason is that
84these components reference material properties, such as thermal conductivity, and currently
85the Modelica design group is discussing a general scheme to describe material properties.
86</p>
87<p>
88For technical details in the design of this library, see the following reference:<br>
89<b>Michael Tiller (2001)</b>: <a href=\"http://www.amazon.de\">
90Introduction to Physical Modeling with Modelica</a>.
91Kluwer Academic Publishers Boston.
92</p>
93<p>
94<b>Acknowledgements:</b><br>
95Several helpful remarks from the following persons are acknowledged:
96John Batteh, Ford Motors, Dearborn, U.S.A;
97<a href=\"http://www.haumer.at/\">Anton Haumer</a>, Technical Consulting & Electrical Engineering, Austria;
98Ludwig Marvan, VA TECH ELIN EBG Elektronik GmbH, Wien, Austria;
99Hans Olsson, Dynasim AB, Sweden;
100Hubertus Tummescheit, Lund Institute of Technology, Lund, Sweden.
101</p>
102<p><b>Copyright &copy; 2001-2007, Modelica Association, Michael Tiller and DLR.</b></p>
103<p><i>
104This Modelica package is free software; it can be redistributed and/or modified
105under the terms of the Modelica license, see the license conditions
106and the accompanying disclaimer in the documentation of package
107Modelica in file \"Modelica/package.mo\".
108</i></p>
109</HTML>
110", revisions="<html>
111<ul>
112<li><i>July 15, 2002</i>
113       by Michael Tiller, <a href=\"http://www.robotic.dlr.de/Martin.Otter/\">Martin Otter</a>
114       and <a href=\"http://www.robotic.dlr.de/Nikolaus.Schuermann/\">Nikolaus Sch&uuml;rmann</a>:<br>
115       Implemented.
116</li>
117<li><i>June 13, 2005</i>
118       by <a href=\"http://www.haumer.at/\">Anton Haumer</a><br>
119       Refined placing of connectors (cosmetic).<br>
120       Refined all Examples; removed Examples.FrequencyInverter, introducing Examples.Motor<br>
121       Introduced temperature dependent correction (1 + alpha*(T - T_ref)) in Fixed/PrescribedHeatFlow<br>
122</li>
123</ul>
124</html>"));
125  package Examples
126    "Example models to demonstrate the usage of package Modelica.Thermal.HeatTransfer" 
127    extends Modelica.Icons.Library2;
128   
129    model TwoMasses "Simple conduction demo" 
130      extends Modelica.Icons.Example;
131      parameter SI.Temperature T_final_K(fixed=false) 
132        "Projected final temperature";
133      parameter NonSI.Temperature_degC T_final_degC(fixed=false) 
134        "Projected final temperature";
135      HeatTransfer.HeatCapacitor mass1(C=15, T(start=from_degC(100))) 
136        annotation (extent=[-100, 20; -40, 80]);
137      HeatTransfer.HeatCapacitor mass2(C=15, T(start=from_degC(0))) annotation (
138         extent=[40, 20; 100, 80]);
139      HeatTransfer.ThermalConductor conduction(G=10) annotation (extent=[-30, -
140            20; 30, 40]);
141      annotation (Documentation(info="<HTML>
142<p>
143This example demonstrates the thermal response of two masses connected by
144a conducting element. The two masses have the same heat capacity but different
145initial temperatures (T1=100 [degC], T2= 0 [degC]). The mass with the higher
146temperature will cool off while the mass with the lower temperature heats up.
147They will each asymptotically approach the calculated temperature <b>T_final_K</b>
148(<b>T_final_degC</b>) that results from dividing the total initial energy in the system by the sum
149of the heat capacities of each element.
150</p>
151<p>
152Simulate for 5 s and plot the variables<br>
153mass1.T, mass2.T, T_final_K or <br>
154Tsensor1.T, Tsensor2.T, T_final_degC
155</p>
156</HTML>
157"),     experiment(StopTime=5),
158        experimentSetupOutput);
159      HeatTransfer.Celsius.TemperatureSensor Tsensor1 annotation (extent=[-60,
160            -80; -20, -40]);
161      HeatTransfer.Celsius.TemperatureSensor Tsensor2 annotation (extent=[60, -
162            80; 20, -40]);
163    equation 
164      connect(mass1.port, conduction.port_a) annotation (points=[-70,20; -70,10;
165            -30,10],      style(color=42));
166      connect(conduction.port_b, mass2.port) annotation (points=[30,10; 70,10;
167            70,20],    style(color=42));
168      connect(mass1.port, Tsensor1.port) annotation (points=[-70,20; -70,-60;
169            -60,-60],    style(color=42));
170      connect(mass2.port, Tsensor2.port) annotation (points=[70, 20; 70, -60;
171            60, -60], style(color=42));
172    initial equation 
173      T_final_K = (mass1.port.T*mass1.C + mass2.port.T*mass2.C)/(mass1.C +
174        mass2.C);
175      T_final_degC = to_degC(T_final_K);
176    end TwoMasses;
177   
178    model ControlledTemperature "Control temperature of a resistor" 
179      extends Modelica.Icons.Example;
180      parameter NonSI.Temperature_degC TAmb=20 "Ambient Temperature";
181      parameter NonSI.Temperature_degC TDif=2 "Error in Temperature";
182      output NonSI.Temperature_degC TRes = to_degC(HeatingResistor1.heatPort.T) 
183        "Resulting Temperature";
184      annotation (Documentation(info="<HTML>
185<P>
186A constant voltage of 10 V is applied to a
187temperature dependent resistor of 10*(1+(T-20C)/(235+20C)) Ohms,
188whose losses v**2/r are dissipated via a
189thermal conductance of 0.1 W/K to ambient temperature 20 degree C.
190The resistor is assumed to have a thermal capacity of 1 J/K,
191having ambient temparature at the beginning of the experiment.
192The temperature of this heating resistor is held by an OnOff-controller
193at reference temperature within a given bandwith +/- 1 K
194by switching on and off the voltage source.
195The reference temperature starts at 25 degree C
196and rises between t = 2 and 8 seconds linear to 50 degree C.
197An approppriate simulating time would be 10 seconds.
198</P>
199</HTML>
200"), Diagram,
201        experiment(StopTime=10),
202        experimentSetupOutput);
203      Modelica.Electrical.Analog.Basic.Ground Ground1
204                                  annotation (extent=[-100, -100; -80, -80]);
205      Modelica.Electrical.Analog.Sources.ConstantVoltage ConstantVoltage1(V=10) 
206                                                            annotation (extent=
207            [-100, -60; -80, -40], rotation=-90);
208      HeatTransfer.HeatCapacitor HeatCapacitor1(C=1, T(start=from_degC(TAmb))) 
209        annotation (extent=[0, -60; 20, -80]);
210      Modelica.Electrical.Analog.Basic.HeatingResistor HeatingResistor1(
211        R_ref=10,
212        T_ref=from_degC(20),
213        alpha=1/(235 + 20)) annotation (extent=[-20, -60; -40, -40], rotation=-
214            90);
215      HeatTransfer.Celsius.FixedTemperature FixedTemperature1(T=TAmb) 
216        annotation (extent=[100, -60; 80, -40]);
217      HeatTransfer.Celsius.TemperatureSensor TemperatureSensor1 annotation (
218          extent=[0, -40; 20, -20], rotation=90);
219      HeatTransfer.ThermalConductor ThermalConductor1(G=0.1) annotation (extent=[40,
220            -60; 60,-40]);
221      Modelica.Electrical.Analog.Ideal.IdealOpeningSwitch IdealSwitch1
222            annotation (extent=[-70, -50; -50, -30]);
223      Modelica.Blocks.Sources.Ramp Ramp1(
224        height=25,
225        duration=6,
226        offset=25,
227        startTime=2) annotation (extent=[40,0; 20,20]);
228      Modelica.Blocks.Logical.OnOffController OnOffController1(bandwidth=TDif) 
229        annotation (extent=[0,-20; -20,0]);
230      Modelica.Blocks.Logical.Not Not1 annotation (extent=[-30,-20; -50,0]);
231    equation 
232      connect(ConstantVoltage1.n, HeatingResistor1.n) annotation (points=[-90,
233            -60; -30, -60], style(color=3));
234      connect(ConstantVoltage1.n, Ground1.p) annotation (points=[-90, -60; -90,
235              -80], style(color=3));
236      connect(HeatingResistor1.heatPort, ThermalConductor1.port_a) annotation (
237          points=[-20,-50; 40,-50],   style(color=42));
238      connect(ThermalConductor1.port_b, FixedTemperature1.port) annotation (
239          points=[60,-50; 80,-50],   style(color=42));
240      connect(HeatingResistor1.heatPort, TemperatureSensor1.port) annotation (
241          points=[-20, -50; 10, -50; 10, -40], style(color=42));
242      connect(HeatingResistor1.heatPort, HeatCapacitor1.port) annotation (
243          points=[-20, -50; 10, -50; 10, -60], style(color=42));
244      connect(ConstantVoltage1.p, IdealSwitch1.p) annotation (points=[-90, -40;
245              -70, -40], style(color=3));
246      connect(IdealSwitch1.n, HeatingResistor1.p) annotation (points=[-50, -40;
247              -30, -40], style(color=3));
248      connect(Ramp1.y, OnOffController1.reference) annotation (points=[19,10;
249            10,10; 10,-4; 2,-4], style(color=74, rgbcolor={0,0,127}));
250      connect(TemperatureSensor1.T, OnOffController1.u) annotation (points=[10,
251            -20; 10,-16; 2,-16], style(color=74, rgbcolor={0,0,127}));
252      connect(OnOffController1.y, Not1.u) annotation (points=[-21,-10; -28,-10],
253          style(color=5, rgbcolor={255,0,255}));
254      connect(Not1.y, IdealSwitch1.control) annotation (points=[-51,-10; -60,
255            -10; -60,-33], style(color=5, rgbcolor={255,0,255}));
256    end ControlledTemperature;
257   
258    model Motor "Second order thermal model of a motor" 
259      extends Modelica.Icons.Example;
260      parameter NonSI.Temperature_degC TAmb = 20 "Ambient temperature";
261      annotation (Documentation(info="<HTML>
262<p>
263This example contains a simple second order thermal model of a motor.
264The periodic power losses are described by table \"lossTable\":<br>
265<table>
266<tr><td valign=\"top\">time</td><td valign=\"top\">winding losses</td><td valign=\"top\">core losses</td></tr>
267<tr><td valign=\"top\">   0</td><td valign=\"top\">           100</td><td valign=\"top\">        500</td></tr>
268<tr><td valign=\"top\"> 360</td><td valign=\"top\">           100</td><td valign=\"top\">        500</td></tr>
269<tr><td valign=\"top\"> 360</td><td valign=\"top\">          1000</td><td valign=\"top\">        500</td></tr>
270<tr><td valign=\"top\"> 600</td><td valign=\"top\">          1000</td><td valign=\"top\">        500</td></tr>
271</table><br>
272Since constant speed is assumed, the core losses keep constant
273whereas the winding losses are low for 6 minutes (no-load) and high for 4 minutes (over load).
274<br>
275The winding losses are corrected by (1 + alpha*(T - T_ref)) because the winding's resistance is temperature dependent whereas the core losses are kept constant (alpha = 0).
276</p>
277<p>
278The power dissipation to the environment is approximated by heat flow through
279a thermal conductance between winding and core,
280partially storage of the heat in the winding's heat capacity
281as well as the core's heat capacity and finally by forced convection to the environment.<br>
282Since constant speed is assumed, the cinvective conductance keeps constant.<br>
283Using Modelica.Thermal.FluidHeatFlow it would be possible to model the coolant air flow, too
284(instead of simple dissipation to a constant ambient's temperature).
285</p>
286<p>
287Simulate for 7200 s; plot Twinding.T and Tcore.T.
288</p>
289</HTML>
290"),     experiment(StopTime=7200),
291        experimentSetupOutput,
292        Diagram);
293      Modelica.Blocks.Sources.CombiTimeTable lossTable(extrapolation=Modelica.
294            Blocks.Types.Extrapolation.Periodic, table=[0,100,500; 360,100,500;
295            360,1000,500; 600,1000,500]) 
296                                annotation (extent=[-50,60; -30,80], rotation=
297            -90);
298      HeatTransfer.PrescribedHeatFlow windingLosses(T_ref=from_degC(95), alpha=
299            3.03E-3)                         annotation (extent=[-90,0; -70,20],
300          rotation=-90);
301      HeatTransfer.HeatCapacitor winding(T(start=from_degC(TAmb)), C=2500) 
302                                            annotation (extent=[-90,-20; -70,
303            -40]);
304      HeatTransfer.Celsius.TemperatureSensor Twinding
305                                                     annotation (extent=[-70,
306            -60; -50,-40], rotation=-90);
307      HeatTransfer.ThermalConductor winding2core(G=10) 
308                                            annotation (extent=[-50,-20; -30,0]);
309      HeatTransfer.PrescribedHeatFlow coreLosses
310                                             annotation (extent=[-10,0; 10,20],
311          rotation=-90);
312      HeatTransfer.HeatCapacitor core(T(start=from_degC(TAmb)), C=25000) 
313                                            annotation (extent=[-10,-20; 10,-40]);
314      HeatTransfer.Celsius.TemperatureSensor Tcore   annotation (extent=[-30,
315            -60; -10,-40],
316                         rotation=-90);
317      Modelica.Blocks.Sources.Constant convectionConstant(k=25) 
318        annotation (extent=[30,20; 50,40], rotation=-90);
319      HeatTransfer.Convection convection annotation (extent=[30,-20; 50,0]);
320      HeatTransfer.Celsius.FixedTemperature environment(T=TAmb) 
321                                                              annotation (
322          extent=[70,-20; 90,0],    rotation=180);
323    equation 
324      connect(windingLosses.port, winding.port)  annotation (points=[-80,0; -80,
325            -20], style(color=42, rgbcolor={191,0,0}));
326      connect(coreLosses.port, core.port)  annotation (points=[6.12303e-016,0;
327            6.12303e-016,-10; 0,-10; 0,-20],
328          style(color=42, rgbcolor={191,0,0}));
329      connect(winding.port, winding2core.port_a) 
330                                       annotation (points=[-80,-20; -80,-10;
331            -50,-10], style(color=42, rgbcolor={191,0,0}));
332      connect(winding2core.port_b, core.port) 
333                                    annotation (points=[-30,-10; 0,-10; 0,-20],
334          style(color=42, rgbcolor={191,0,0}));
335      connect(winding.port, Twinding.port)  annotation (points=[-80,-20; -80,
336            -10; -60,-10; -60,-40], style(color=42, rgbcolor={191,0,0}));
337      connect(core.port, Tcore.port)  annotation (points=[0,-20; 0,-10; -20,-10;
338            -20,-40],      style(color=42, rgbcolor={191,0,0}));
339      connect(winding2core.port_b, convection.solid) 
340                                          annotation (points=[-30,-10; 30,-10],
341          style(color=42, rgbcolor={191,0,0}));
342      connect(convection.fluid, environment.port) annotation (points=[50,-10;
343            60,-10; 60,-10; 70,-10], style(color=42, rgbcolor={191,0,0}));
344      connect(convectionConstant.y, convection.Gc) 
345        annotation (points=[40,19; 40,0], style(color=74, rgbcolor={0,0,127}));
346      connect(lossTable.y[1], windingLosses.Q_flow) annotation (points=[-40,59;
347            -40,40; -80,40; -80,20], style(color=74, rgbcolor={0,0,127}));
348      connect(lossTable.y[2], coreLosses.Q_flow) annotation (points=[-40,59;
349            -40,40; -6.12303e-016,40; -6.12303e-016,20],
350                                   style(color=74, rgbcolor={0,0,127}));
351    end Motor;
352    annotation (Icon(
353         Ellipse(extent=[-60,10; 40,-90], style(color=10, rgbcolor={135,135,135})),
354          Polygon(points=[-30,-12; -30,-68; 28,-40; -30,-12], style(
355            color=10,
356            rgbcolor={135,135,135},
357            fillColor=10,
358            rgbfillColor={135,135,135},
359            fillPattern=1))), Documentation(info="<html>
360 
361</html>"));
362  end Examples;
363 
364  package Interfaces "Connectors and partial models" 
365   
366    extends Modelica.Icons.Library2;
367   
368    partial connector HeatPort "Thermal port for 1-dim. heat transfer" 
369      SI.Temperature T "Port temperature";
370      flow SI.HeatFlowRate Q_flow
371        "Heat flow rate (positive if flowing from outside into the component)";
372      annotation (Documentation(info="<html>
373 
374</html>"));
375    end HeatPort;
376   
377    connector HeatPort_a
378      "Thermal port for 1-dim. heat transfer (filled rectangular icon)" 
379     
380      extends HeatPort;
381     
382      annotation(defaultComponentName = "port_a",
383        Documentation(info="<HTML>
384<p>This connector is used for 1-dimensional heat flow between components.
385The variables in the connector are:</p>
386<pre>   
387   T       Temperature in [Kelvin].
388   Q_flow  Heat flow rate in [Watt].
389</pre>
390<p>According to the Modelica sign convention, a <b>positive</b> heat flow
391rate <b>Q_flow</b> is considered to flow <b>into</b> a component. This
392convention has to be used whenever this connector is used in a model
393class.</p>
394<p>Note, that the two connector classes <b>HeatPort_a</b> and
395<b>HeatPort_b</b> are identical with the only exception of the different
396<b>icon layout</b>.</p></HTML>
397"),     Icon(Rectangle(extent=[-100, 100; 100, -100], style(color=42, fillColor=
398                 42))),
399        Diagram(Rectangle(extent=[-50,50; 50,-50],   style(color=42,
400                fillColor=42)), Text(
401            extent=[-120,120; 100,60],
402            string="%name",
403            style(color=42))));
404    end HeatPort_a;
405   
406    connector HeatPort_b
407      "Thermal port for 1-dim. heat transfer (unfilled rectangular icon)" 
408     
409      extends HeatPort;
410     
411      annotation(defaultComponentName = "port_b",
412        Documentation(info="<HTML>
413<p>This connector is used for 1-dimensional heat flow between components.
414The variables in the connector are:</p>
415<pre>
416   T       Temperature in [Kelvin].
417   Q_flow  Heat flow rate in [Watt].
418</pre>
419<p>According to the Modelica sign convention, a <b>positive</b> heat flow
420rate <b>Q_flow</b> is considered to flow <b>into</b> a component. This
421convention has to be used whenever this connector is used in a model
422class.</p>
423<p>Note, that the two connector classes <b>HeatPort_a</b> and
424<b>HeatPort_b</b> are identical with the only exception of the different
425<b>icon layout</b>.</p></HTML>
426"),     Diagram(Rectangle(extent=[-50,50; 50,-50],    style(color=42,
427                fillColor=7)), Text(
428            extent=[-100,120; 120,60],
429            string="%name",
430            style(color=42))),
431        Icon(Rectangle(extent=[-100, 100; 100, -100], style(color=42, fillColor=
432                 7))));
433    end HeatPort_b;
434   
435    partial model Element1D
436      "Partial heat transfer element with two HeatPort connectors that does not store energy" 
437     
438      SI.HeatFlowRate Q_flow "Heat flow rate from port_a -> port_b";
439      SI.TemperatureDifference dT "port_a.T - port_b.T";
440    public 
441      HeatPort_a port_a annotation (extent=[-110,-10; -90,10]);
442      HeatPort_b port_b annotation (extent=[90,-10; 110,10]);
443      annotation (Documentation(info="<HTML>
444<p>
445This partial model contains the basic connectors and variables to
446allow heat transfer models to be created that <b>do not store energy</b>,
447This model defines and includes equations for the temperature
448drop across the element, <b>dT</b>, and the heat flow rate
449through the element from port_a to port_b, <b>Q_flow</b>.
450</p>
451<p>
452By extending this model, it is possible to write simple
453constitutive equations for many types of heat transfer components.
454</p>
455</HTML>
456"), Icon,
457        Diagram);
458    equation 
459      dT = port_a.T - port_b.T;
460      port_a.Q_flow = Q_flow;
461      port_b.Q_flow = -Q_flow;
462    end Element1D;
463    annotation (Icon(
464              Rectangle(extent=[-60,10; 40,-90],   style(color=42,
465              fillColor=42))), Documentation(info="<html>
466 
467</html>"));
468  end Interfaces;
469 
470  model HeatCapacitor "Lumped thermal element storing heat" 
471    parameter SI.HeatCapacity C "Heat capacity of part (= cp*m)";
472    parameter Boolean steadyStateStart=false 
473      "true, if component shall start in steady state";
474    SI.Temperature T(start=from_degC(20)) "Temperature of part";
475    annotation (
476      Icon(
477        Text(extent=[-129, 121; 131, 70], string="%name"),
478        Polygon(points=[0,67; -20,63; -40,57; -52,43; -58,35; -68,25; -72,13;
479              -76,-1; -78,-15; -76,-31; -76,-43; -76,-53; -70,-65; -64,-73; -48,
480              -77; -30,-83