modelSimpleHouse1

Building wall model

Extends from SimpleHouse0 (Start file for simple house example).

Information

A very simple building envelope model will be constructed manually using thermal resistors and heat capacitors. The house consists of a wall represented by a single heat capacitor and a thermal resistor. The boundary temperature are already included in Buildings.Examples.Tutorial.SimpleHouse.SimpleHouse0. The wall has a surface area of Awall=100 m2, a thickness of dwall=25 cm, a thermal conductivity of kwall=0.04 W/(m K), a density of ρwall=2000 kg/m3, and a specific heat capacity of cp,wall= 1000 J/(kg K)

These parameters are already declared in the equation section of Buildings.Examples.Tutorial.SimpleHouse.SimpleHouse0. You can use this way of declaring parameters in the remainder of this exercise, but this is not required.

The conductive thermal resistance value of a wall may be computed as R=d/(A*k). The heat capacity value of a wall may be computed as C=A*d*cp

Required models

Connection instructions

Connect one side of the thermal resistor to the output of PrescribedTemperature and the other side of the thermal resistor to the heat capacitor.

Reference result

If you correctly added the model of the heat capacitor, connected it to the resistor and added the parameter values for C, then you should be able to simulate the model. To do this, press the Simulation Setup and set the model Stop time to 1e6 seconds. You can now simulate the model by pressing the Simulate button.

You can plot individual variables values by clicking on their name in the variable browser on the left. Now plot the wall capacitor temperature value T. It should look like the figure below (1 Ms is around 12 days).

Wall temperature as function of time.

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.AreaAWall (from SimpleHouse0)100Wall area
Modelica.Units.SI.LengthdWall (from SimpleHouse0)0.25Wall thickness
Modelica.Units.SI.ThermalConductivitykWall (from SimpleHouse0)0.04Wall thermal conductivity
Modelica.Units.SI.DensityrhoWall (from SimpleHouse0)2000Wall density
Modelica.Units.SI.SpecificHeatCapacitycpWall (from SimpleHouse0)1000Wall specific heat capacity

Connectors

TypeNameDefaultDescription
Buildings.BoundaryConditions.WeatherData.BusweaBus (from SimpleHouse0)Weather data bus

Components

TypeNameDefaultDescription
Buildings.BoundaryConditions.WeatherData.ReaderTMY3weaDat (from SimpleHouse0)Weather data reader
Buildings.HeatTransfer.Sources.PrescribedTemperatureTOut (from SimpleHouse0)Exterior temperature boundary condition
Modelica.Thermal.HeatTransfer.Components.HeatCapacitorwalCapThermal mass of wall
Modelica.Thermal.HeatTransfer.Components.ThermalResistorwalResThermal resistor for wall: 25 cm of rockwool

Revisions

  • September 4, 2023, by Jelger Jansen:
    First implementation.