This function computes a fictitious thermal resistance between the pipe outer wall and a fictitious, average temperature of the plane that contains the pipes. The equation is the same as is implemented in TRNSYS 17. Different equations are used for
sysTyp ==
Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Floor
),sysTyp ==
Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Ceiling_Wall_or_Capillary
and disPip/dPipOut ≥ 5.8
), andsysTyp ==
Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Ceiling_Wall_or_Capillary
and disPip/dPipOut < 5.8
).The resistance Rx
is based on a steady-state heat
transfer analysis. Therefore, it is only valid during steady-state.
For a fully dynamic model, a finite element method for the radiant
slab would need to be implemented.
function AverageResistance input Modelica.SIunits.Distance disPip "pipe distance"; input Modelica.SIunits.Diameter dPipOut "pipe outside diameter"; input Modelica.SIunits.ThermalConductivity k "pipe level construction element thermal conductivity"; input Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType sysTyp "Type of radiant system"; input Modelica.SIunits.ThermalConductivity kIns "floor slab insulation thermal conductivity"; input Modelica.SIunits.Thickness dIns "floor slab insulation thickness"; output Modelica.SIunits.ThermalInsulance Rx "Thermal insulance"; end AverageResistance;
1/s
in computation of
infSum
.