ThermalConductor

model ThermalConductor "Lumped thermal element transporting heat without storing it"
    extends Interfaces.Element1D;

    parameter SI.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    <blockquote><pre>\nG = k*A/L\nk: Thermal conductivity (material constant)\nA: Area of box\nL: Length of box\n    </pre></blockquote>\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    <blockquote><pre>\nG = 2*pi*k*L/log(r_out/r_in)\npi   : Modelica.Constants.pi\nk    : Thermal conductivity (material constant)\nL    : Length of cylinder\nlog  : Modelica.Math.log;\nr_out: Outer radius of cylinder\nr_in : Inner radius of cylinder\n    </pre></blockquote>\n    </li>\n</ul>\n<blockquote><pre>\nTypical 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></blockquote>\n</html>"));
end ThermalConductor;