modelSpaceCooling

Space cooling system

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

Information

This block is identical to Buildings.Examples.Tutorial.SpaceCooling.System3, except that an air filter is added to the cooling system.

The major input signals for the air filter are configured as follows:

  • The input trace substance C_inflow.y changes from 10 µg/m³ (7.73e-9 kg/kg, assuming an air density of 1.293 kg/m³) to 15 µg/m³ (1.16e-8 kg/kg) at 12:00 (15552000+12*3600 seconds).
  • The filter replacement signal repSig is false.

The expected output are:

  • The filtration efficiency airFil.eps[1] decreases along with the contaminant airFil.masAcc.mCon build up.
  • The fan power fan.P slightly increases, caused by the rising pressure drop across the filter as contaminants build up.

Note that these changes in filtration efficiency and pressure drop are relatively minor over the span of a single day, with more pronounced effects expected over months.

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.VolumeV6*10*3Room volume
Realeps0.8Heat recovery effectiveness
Modelica.Units.SI.TemperatureTASup_nominal291.15Nominal air temperature supplied to room
Modelica.Units.SI.DimensionlessRatiowASup_nominal0.012Nominal air humidity ratio supplied to room [kg/kg] assuming 90% relative humidity
Modelica.Units.SI.TemperatureTRooSet297.15Nominal room air temperature
Modelica.Units.SI.TemperatureTOut_nominal303.15Design outlet air temperature
Modelica.Units.SI.TemperatureTHeaRecLvgTOut_nominal - eps*(TOut_nominal - TRooSet)Air temperature leaving the heat recovery
Modelica.Units.SI.DimensionlessRatiowHeaRecLvg0.0135Air humidity ratio leaving the heat recovery [kg/kg]
Modelica.Units.SI.HeatFlowRateQRooInt_flow1000Internal heat gains of the room
Modelica.Units.SI.HeatFlowRateQRooC_flow_nominal-QRooInt_flow - 10E3/30*(TOut_nominal - TRooSet)Nominal cooling load of the room
Modelica.Units.SI.MassFlowRatemA_flow_nominal1.3*QRooC_flow_nominal/1006/(TASup_nominal - TRooSet)Nominal air mass flow rate, increased by factor 1.3 to allow for recovery after temperature setback
Modelica.Units.SI.TemperatureDifferencedTFan2Estimated temperature raise across fan that needs to be made up by the cooling coil
Modelica.Units.SI.HeatFlowRateQCoiC_flow_nominalmA_flow_nominal*(TASup_nominal - THeaRecLvg - dTFan)*1006 + mA_flow_nominal*(wASup_nominal - wHeaRecLvg)*2458.3e3Cooling load of coil, taking into account outside air sensible and latent heat removal
Modelica.Units.SI.TemperatureTWSup_nominal285.15Water supply temperature
Modelica.Units.SI.TemperatureTWRet_nominal289.15Water return temperature
Modelica.Units.SI.MassFlowRatemW_flow_nominal-QCoiC_flow_nominal/(TWRet_nominal - TWSup_nominal)/4200Nominal water mass flow rate
Buildings.Fluid.AirFilters.Data.GenericperPerformance dataset of the air filter

Connectors

TypeNameDefaultDescription
BoundaryConditions.WeatherData.BusweaBus

Components

TypeNameDefaultDescription
Buildings.Fluid.MixingVolumes.MixingVolumevol
Modelica.Thermal.HeatTransfer.Components.ThermalConductortheConThermal conductance with the ambient
Modelica.Thermal.HeatTransfer.Sources.PrescribedTemperatureTOutOutside temperature
Modelica.Thermal.HeatTransfer.Sources.FixedHeatFlowpreHeaPrescribed heat flow
Buildings.Fluid.Movers.FlowControlled_m_flowfanSupply air fan
Buildings.Fluid.HeatExchangers.ConstantEffectivenesshexHeat recovery
Buildings.Fluid.HeatExchangers.WetCoilEffectivenessNTUcooCoiCooling coil
Buildings.Fluid.Sources.Outsideout
Buildings.Fluid.Sources.MassFlowSource_TsouWatSource for water flow rate
Buildings.Fluid.Sources.Boundary_pTsinWatSink for water circuit
BoundaryConditions.WeatherData.ReaderTMY3weaDatWeather data reader
Buildings.Controls.OBC.CDL.Reals.Sources.ConstantmAir_flowFan air flow rate
Buildings.Fluid.Sensors.TemperatureTwoPortsenTemHXOutTemperature sensor for heat recovery outlet on supply side
Buildings.Fluid.Sensors.TemperatureTwoPortsenTemSupAirTemperature sensor for supply air
Buildings.Controls.OBC.CDL.Reals.Sources.ConstantTRooSetPoiRoom temperature set point
Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensorsenTemRooRoom temperature sensor
Buildings.Controls.Continuous.LimPIDconRooRoom controller
Buildings.Fluid.AirFilters.EmpiricalairFilAir filter
Modelica.Blocks.Sources.RampC_inflowContaminant mass flow rate fraction
Buildings.Fluid.Sensors.TraceSubstancesTwoPortC_outTrace substance sensor of outlet air
Buildings.Controls.OBC.CDL.Logical.Sources.ConstantrepSigFilter replacement signal
Buildings.Controls.OBC.CDL.Reals.SubtractsubDifSubstance difference between inlet and outlet

Contents

NameDescription
MediumAMedium for air
MediumWMedium for water

Revisions