model PressureReducingValve
parameter Modelica.SIunits.Pressure SetPressure = 1e+7 "Set pressure (relative value)";
parameter Modelica.SIunits.Pressure Deviation = -500000 "Deviation";
parameter Real gain = 1 "Controller gain";
extends HydraulicsByFluidon.Components.Valves.Base.PartialPressureFlowValve;
equation
ssU = min(1, (SetPressure + environment.pAmbient + volumeFlowA / NominalVolumeFlow * Deviation - fluidPortB.p) * (1e-5) * gain);
annotation (
Icon(
coordinateSystem(
extent = {
{-100, -100},
{100, 100}},
preserveAspectRatio = false),
graphics = {
Rectangle(
fillColor = {255, 255, 255},
fillPattern = FillPattern.Solid,
extent = {
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Line(
origin = {0, -10},
points = {
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fillPattern = FillPattern.Solid,
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Documentation(info = "<html>\n <p>\n The component PressureReducingValve is a model of a 2-port pressure control valve. \n It maintains a largely constant outlet pressure even at a variable (higher) inlet pressure.\n </p>\n <p>\n <center><img src=\"modelica://HydraulicsByFluidon/Resources/Images/Components/Valves/PressureValves/PressureReducingValve.png\"></center>\n </p>\n <p>\n If inlet pressure <var>pA</var> is less than <var>Set pressure (relative value)</var> the valve acts like an orifice \n with the characteristics <var>Nominal volume flow</var> and <var>Nominal pressure difference</var>.\n </p>\n <p>\n For all pressures exceeding <var>Set pressure (relative value)</var> the valve opens and \n the flow increases linearly following the slope given by parameters <var>Nominal volume flow</var> and \n <var>Pressure drop</var>. The outlet pressure deviates by <var>Deviation P-A</var> @ <var>Nominal volume flow</var>.\n </p>\n <p>\n <center><img src=\"modelica://HydraulicsByFluidon/Resources/Images/Components/Valves/PressureValves/PressureReducingValveReducing.png\"></center>\n </p>\n <p>\n The component PressureReducingValve is not a model of a pressure control valve according to its \n physical structure. It merely represents the characteristic behavior of a pressure reducing \n valve. Therefore dynamic effects such as forces due to inertia will not be represented.\n </p>\n </html>"));
end PressureReducingValve;