model AnnularGap "Annular Gap"
import HydraulicsByFluidon.Media.Base.FluidInterface;
import Modelica.Units.SI;
parameter SI.Length Diameter(min = 0, displayUnit = "mm") = 0.005 "Outer diameter";
parameter SI.Length GapHeightA(min = 0, displayUnit = "mum") = 1e-4 "Gap Height A";
parameter SI.Length GapHeightB(min = 1e-6, displayUnit = "mum") = 1e-4 "Gap Heigt B";
parameter SI.Length Length(displayUnit = "mm") = 0.1 "Length";
parameter SI.DimensionlessRatio relEccentricity(min = 0, max = 1, displayUnit = "%") = 0 "Eccentricity ratio";
extends HydraulicsByFluidon.Components.Base.PartialResistorBase;
protected
Real pMid;
Real lambda;
Real minGapHeight;
initial equation
assert(0 < GapHeightA, "Gap Height B must be > 0");
assert(0 < GapHeightB, "Gap Height A must be > 0");
equation
lambda = minGapHeight / max(GapHeightA, GapHeightB);
pMid = 0.5 * (fluidPortA.p + fluidPortB.p);
minGapHeight = min(GapHeightA, GapHeightB);
fluidPortB.mFlow = Modelica.Constants.pi * Diameter * minGapHeight ^ 3 / (12 * Length * FluidInterface.calcNu(fluidPortA.fluidId, pMid, fluidPortA.fluidTemperature)) * (2 * lambda ^ 2 / (1 + lambda) + (1 + lambda) * (0.75) * relEccentricity ^ 2) * dp;
annotation (
Icon(graphics = {
Rectangle(
fillColor = {255, 255, 255},
fillPattern = FillPattern.Solid,
extent = {
{-30, 60},
{30, -60}}),
Polygon(
fillColor = {200, 200, 200},
fillPattern = FillPattern.Solid,
points = {
{-20, 60},
{-14, -60},
{14, -60},
{20, 60},
{-20, 60}}),
Text(
origin = {0, -42},
textColor = {0, 0, 255},
extent = {
{-78, -20},
{78, 20}},
textString = "A"),
Text(
origin = {0, 42},
textColor = {0, 0, 255},
extent = {
{-78, -20},
{78, 20}},
textString = "B")}),
Documentation(info = "<html>\r\r\r\r\r\n <p>\r\r\r\r\r\n The component AnnularOrifice is a model of a flow resistance of a fully-developed laminar flow in the gap of a circular tube with an insert.\r\r\r\r\r\n The insert can be located off-center from the tube by the <var>Eccentricity ratio</var>.\r\r\r\r\r\n </p>\r\r\r\r\r\n <p>\r\r\r\r\r\n <center><img align=\"middle\" src=\"modelica://HydraulicsByFluidon/Resources/Images/Components/Resistors/AnnularOrifice.png\"></center>\r\r\r\r\r\n </p>\r\r\r\r\r\n <p>\r\r\r\r\r\n The <var>Eccentricity ratio</var> is defined by\r\r\r\r\r\n </p>\r\r\r\r\r\n <p>\r\r\r\r\r\n <var>Eccentricity ratio</var> = eccentricity / min(<var>Gap Height A</var>, <var>Gap Height B</var>), 0 <= <var>Eccentricity ratio</var> <= 1\r\r\r\r\r\n </p></html>"));
end AnnularGap;