modelMultipoleThermalResistances_OneUTube

Validation of the thermal resitances for a single U-tube borehole

Extends from Modelica.Icons.Example (Icon for runnable examples).

Information

This example validates the implementation of AixLib.Fluid.Geothermal.Borefields.BaseClasses.Boreholes.BaseClasses.Functions.multipoleThermalResistances for the evaluation of the borehole thermal resistances.

The multipole method is used to evaluate thermal resistances for a single U-tube borehole with asymmetrically positionned pipes. Results are compared to reference values given in Claesson and Hellström (2011).

References

Claesson, J., & Hellström, G. (2011). Multipole method to calculate borehole thermal resistances in a borehole heat exchanger. HVAC&R Research, 17(6), 895-911.

Parameters

TypeNameDefaultDescription
IntegernPip2Number of pipes
IntegerJ3Number of multipoles
Modelica.Units.SI.PositionxPip{0.03, -0.03}x-Coordinates of pipes
Modelica.Units.SI.PositionyPip{0.00, 0.02}y-Coordinates of pipes
Modelica.Units.SI.RadiusrBor0.07Borehole radius
Modelica.Units.SI.RadiusrPipfill(0.02, nPip)Outter radius of pipes
Modelica.Units.SI.ThermalConductivitykFil1.5Thermal conductivity of grouting material
Modelica.Units.SI.ThermalConductivitykSoi2.5Thermal conductivity of soil material
RealRFluPipfill(1.2/(2*Modelica.Constants.pi*kFil), nPip)Fluid to pipe wall thermal resistances
Modelica.Units.SI.TemperatureTBor0Average borehole wall temperature
RealRDelta_Ref{{1/3.680, 1/0.242}, {1/0.242, 1/3.724}}Reference delta-circuit thermal resistances
RealR_Ref{{0.25592, 0.01561}, {0.01561, 0.25311}}Reference internal thermal resistances

Components

TypeNameDefaultDescription
RealRDeltaDelta-circuit thermal resistances
RealRInternal thermal resistances

Revisions

  • June 21, 2018, by Massimo Cimmino:
    First implementation.