model ThermalConductor "Lumped thermal element transporting heat without storing it"
extends Interfaces.Element1D;
parameter Modelica.SIunits.ThermalConductance G "Constant thermal conductance of material";
equation
Q_flow = G * dT;
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Documentation(info = "<html>\n<p>\nThis is a model for transport of heat without storing it; see also:\n<a href=\"modelica://Modelica.Thermal.HeatTransfer.Components.ThermalResistor\">ThermalResistor</a>.\nIt may be used for complicated geometries where\nthe thermal conductance G (= inverse of thermal resistance)\nis determined by measurements and is assumed to be constant\nover the range of operations. If the component consists mainly of\none type of material and a regular geometry, it may be calculated,\ne.g., with one of the following equations:\n</p>\n<ul>\n<li><p>\n Conductance for a <strong>box</strong> geometry under the assumption\n that heat flows along the box length:</p>\n <pre>\n G = k*A/L\n k: Thermal conductivity (material constant)\n A: Area of box\n L: Length of box\n </pre>\n </li>\n<li><p>\n Conductance for a <strong>cylindrical</strong> geometry under the assumption\n that heat flows from the inside to the outside radius\n of the cylinder:</p>\n <pre>\n G = 2*pi*k*L/log(r_out/r_in)\n pi : Modelica.Constants.pi\n k : Thermal conductivity (material constant)\n L : Length of cylinder\n log : Modelica.Math.log;\n r_out: Outer radius of cylinder\n r_in : Inner radius of cylinder\n </pre>\n </li>\n</ul>\n<pre>\n Typical values for k at 20 degC in W/(m.K):\n aluminium 220\n concrete 1\n copper 384\n iron 74\n silver 407\n steel 45 .. 15 (V2A)\n wood 0.1 ... 0.2\n</pre>\n</html>"));
end ThermalConductor;