modelWellMixedAir

Zone air model assuming perfectly mixed air

Extends from IDEAS.Buildings.Components.ZoneAirModels.BaseClasses.PartialAirModel.

Information

Perfectly mixed air model.

Main equations

This model computes a single air temperature that is used to evaluate convective heat transfer of all surfaces, components connected to gainCon (e.g. radiators), etc. The air outlet temperature equals the well mixed air temperature.

Assumption and limitations

This model is not valid for buildings where stratification occurs, e.g. when using floor cooling or ceiling heating.

When dry air is used, then the relative humidity output is set to zero.

Typical use and important parameters

The zone air volume Vto determines the thermal mass of the air. This mass may be artificially increased using mSenFac if desired, e.g. to take into account the thermal mass of furniture.

Dynamics

This model only contains states to represent the energy and mass dynamics, typically using a temperature and pressure variable. Parameters energyDynamics and massDynamics may be used to change the model dynamics.

Validation

See BESTEST.

Parameters

TypeNameDefaultDescription
StateSelectstateSelectTVolif sim.linearise then StateSelect.prefer else StateSelect.defaultSet to .prefer to use temperature as a state in mixing volume

Components

TypeNameDefaultDescription
RealACH(sum(m_flow_pos)*3600/rho_default)/VtotAir change rate per hour

Contents

NameDescription
MixingVolumeNominalprotectedTo avoid warning when modifying parameters of protected submodel dynBal of MixingVolumeMoistAir

Revisions

  • March 21, 2022 by Filip Jorissen:
    Disabled latent heat gains when the medium contains no water. #1251.
  • November 21, 2020 by Filip Jorissen:
    Avoiding warnings for one port sensors.
  • December 13, 2019 by Filip Jorissen:
    Directly referencing IDEAS.Media.Air instead of Medium to avoid warnings in Dymola and errors in OpenModelica. #1097.
  • March 29, 2019 by Filip Jorissen:
    Added start value for CO2 concentration for #1004.
  • February 14, 2019 by Filip Jorissen:
    Changed default value of stateSelectTVol. See #982.
  • December 11, 2018 by Filip Jorissen:
    Revised mixing volume connection order to avoid triggering flow reversal warnings. See #964.
  • August 30, 2018 by Damien Picard:
    Added constant StateSelectTVol to be able to select preferred state of mixing volume. See #905.
  • July 27, 2018 by Filip Jorissen:
    Added nominal values for m, mXi and mC. See #864.
  • Added output for the CO2 concentration. See #868.
  • April 27, 2018 by Filip Jorissen:
    Created MixingVolumeNominalU such that MixingVolume can be used without generating a warning.
  • April 27, 2018 by Filip Jorissen:
    Added nominal value for internal energy of mixing volume. See #797.
  • Modified model for supporting new interzonal air flow models. Air leakage model and its parameters have been removed. See #796.
  • August 5, 2017 by Filip Jorissen:
    Added support for dry air.
  • November 15, 2016 by Filip Jorissen:
    Revised documentation.
  • August 26, 2016 by Filip Jorissen:
    Added support for conservation of energy.
  • April 30, 2016, by Filip Jorissen:
    First implementation.