modelHeatConduction3D

Model for 3D heat conduction

Extends from BuildingSystems.HAM.HeatConduction.BaseClasses.HeatConductionGeneral (General model for heat conduction of a body).

Information

This is a model which describes the three-dimensional heat conduction in x-, y- and z-direction within a cuboid shaped body width the edge length dx, dy and dz

c ρ dx dy dz dT ⁄ dt = Q̇x1 + Q̇x2 + Q̇y1 + Q̇y2 + Q̇z1 + Q̇z2 + Q̇heatsource,

with the heat flow rates to the borders x1/y2, y1/y2 and z1/z2

x1/x2; = kx (Tx1/x2 - T).

y1/y2; = ky (Ty1/y2 - T).

z1/z2; = kz (Tz1/z2 - T).

Here kx, kY and kz are the thermal conductances in the x-, y- and z-dimension

kx = 2 λ ⁄ dx dy dz.

ky = 2 λ ⁄ dy dx dz.

kz = 2 λ ⁄ dz dy dx.

c is the specific heat capacity, ρ the density, λ the heat conductivity, Q̇heatsource an optional heat source within the body. Tx1/x2, Ty1/y2 and Tz1/z2 are the temperatures on the borders x1/x2, y1/y2 and z1/z2 with the areas dy dz, dx dz and dy dx.

Notes

For problems with 1 dimensional heat conduction, the simplified model BuildingSystems.HAM.HeatConduction.HeatConduction1D can be used and combined with other models from the BuildingSystems library.

Parameters

TypeNameDefaultDescription
General
BuildingSystems.HAM.Data.MaterialProperties.BaseClasses.MaterialThermalGeneralmaterial (from HeatConductionGeneral)Material of the body
General › Geometry
Modelica.Units.SI.LengthlengthX (from HeatConductionGeneral)1.0Length in x dimension
Advanced › Inner hollow spaces
Modelica.Units.SI.AreaARedXY0.0Reduction area for heat conduction caused by inner hollow spaces in the xy plane
Modelica.Units.SI.AreaARedXZ0.0Reduction area for heat conduction caused by inner hollow spaces in the xz plane
Modelica.Units.SI.AreaARedYZ0.0Reduction area for heat conduction caused by inner hollow spaces in the yz plane
Modelica.Units.SI.VolumeVRed0.0Reduction volume for the thermal heat capacity caused by inner hollow spaces
RealgeoFacX1.0Geometry factor for heat conduction caused by inner hollow spaces in x dimension
RealgeoFacY1.0Geometry factor for heat conduction caused by inner hollow spaces in y dimension
RealgeoFacZ1.0Geometry factor for heat conduction caused by inner spaces in z dimension
Initialization
Modelica.Units.SI.TemperatureT_start293.15Start temperature of the thermal node

Connectors

TypeNameDefaultDescription
BuildingSystems.Interfaces.HeatPortheatPort_x1Heat port in direction x1
BuildingSystems.Interfaces.HeatPortheatPort_x2Heat port in direction x2
BuildingSystems.Interfaces.HeatPortheatPort_y1Heat port in direction y1
BuildingSystems.Interfaces.HeatPortheatPort_y2Heat port in direction y2
BuildingSystems.Interfaces.HeatPortheatPort_z1Heat port in direction z1
BuildingSystems.Interfaces.HeatPortheatPort_z2Heat port in direction z2
BuildingSystems.Interfaces.HeatPortheatPort_sourceOptional heat source at the thermal node

Components

TypeNameDefaultDescription
Modelica.Units.SI.LengthlengthY (from HeatConductionGeneral)1.0Length in y dimension
Modelica.Units.SI.LengthlengthZ (from HeatConductionGeneral)1.0Length in z dimension
Modelica.Units.SI.TemperatureTTemperature of the thermal node

Revisions

  • April 24, 2019 by Christoph Nytsch-Geusen:
    Adaptation to flexible geometries.
  • May 23, 2016 by Christoph Nytsch-Geusen:
    First implementation.