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I have been trying for a while now to model an evaporator for a steam cycle. The main issue I am running into is I can not get water to change phase. Generally it just reaches the saturation temp and never goes above it not matter how much heat I add. I have tried using the dynamic pipe and basic HX in the fluids library as well as components from thermopower. Is there some trick I am missing?
model DynamicPipeHT
package Medium = Modelica.Media.Water.StandardWater();
replaceable model HeatTransfer = Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.LocalPipeFlowHeatTransfer();
constrainedby
Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.PartialFlowHeatTransfer;
Modelica.Fluid.Pipes.DynamicPipe pipe(redeclare package Medium = Medium, redeclare model HeatTransfer = HeatTransfer, diameter = 0.0125, length = 3, nNodes = 6, use_HeatTransfer = true) annotation(
Placement(visible = true, transformation(origin = {-16, 10}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
Modelica.Fluid.Sources.FixedBoundary Sink(redeclare package Medium = Medium, nPorts = 1) annotation(
Placement(visible = true, transformation(origin = {50, 10}, extent = {{10, -10}, {-10, 10}}, rotation = 0)));
Modelica.Fluid.Sources.MassFlowSource_T MassFlowSource(redeclare package Medium = Medium, m_flow = 0.05, nPorts = 1) annotation(
Placement(visible = true, transformation(origin = {-62, 10}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
inner Modelica.Fluid.System system annotation(
Placement(visible = true, transformation(origin = {-214, 68}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
Modelica.Thermal.HeatTransfer.Sources.FixedHeatFlow fixedHeatFlow(Q_flow = 15000, alpha = 0.001) annotation(
Placement(visible = true, transformation(origin = {-86, 60}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
Modelica.Fluid.Sensors.TemperatureTwoPort temperature(redeclare package Medium = Medium) annotation(
Placement(visible = true, transformation(origin = {16, 10}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
Modelica.Thermal.HeatTransfer.Components.ThermalConductor thermalConductor(G = 42.3) annotation(
Placement(visible = true, transformation(origin = {-16, 36}, extent = {{-10, -10}, {10, 10}}, rotation = -90)));
Modelica.Fluid.Sensors.SpecificEnthalpy specificEnthalpy(redeclare package Medium = Medium) annotation(
Placement(visible = true, transformation(origin = {30, 42}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
equation
connect(MassFlowSource.ports[1], pipe.port_a) annotation(
Line(points = {{-52, 10}, {-26, 10}, {-26, 10}, {-26, 10}}, color = {0, 127, 255}));
connect(pipe.port_b, temperature.port_a) annotation(
Line(points = {{-6, 10}, {6, 10}, {6, 10}, {6, 10}}, color = {0, 127, 255}));
connect(temperature.port_b, Sink.ports[1]) annotation(
Line(points = {{26, 10}, {40, 10}, {40, 10}, {40, 10}}, color = {0, 127, 255}));
connect(thermalConductor.port_b, pipe.heatPorts[1]) annotation(
Line(points = {{-16, 26}, {-16, 26}, {-16, 14}, {-16, 14}}, color = {191, 0, 0}));
connect(fixedHeatFlow.port, thermalConductor.port_a) annotation(
Line(points = {{-76, 60}, {-16, 60}, {-16, 46}, {-16, 46}}, color = {191, 0, 0}));
connect(temperature.port_b, specificEnthalpy.port) annotation(
Line(points = {{26, 10}, {30, 10}, {30, 32}}, color = {0, 127, 255}));
annotation(
uses(Modelica(version = "3.2.3")));
end DynamicPipeHT;
Are there any examples of modeling a Rankine Cycle in openModelica anywhere using the Fluids library? The example in thermopower does not work for me. I have been trying to use the fluids library but have been running into issues, particularly with how to model the evaporator in the cycle. I have tried using the basix HX and the dynamic pipe with Standard Water as the medium but whenever I add enough heat to change phase it errors out.
Is there a way to get the Mineral Oil within the Thermal Library to work with blocks from the Fluid library? I am trying to model a heat exchanger where one side is mineral oil and other is water using the BasicHX block. I cant seem to get it to work with mineral oil. I can get it to work with water as working fluid on both sides but it doesnt like it when I change the one side to mineral oil.
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