modelMediumColumnDynamic

Vertical shaft with no friction and storage of heat and mass

Extends from Buildings.Fluid.Interfaces.LumpedVolumeDeclarations.

Information

This model contains a completely mixed fluid volume and models that take into account the pressure difference of a medium column that is at the same temperature as the fluid volume. It can be used to model the pressure difference caused by a stack effect.

Typical use and important parameters

Set the parameter use_HeatTransfer=true to expose a heatPort. This heatPort can be used to add or subtract heat from the volume. This allows, for example, to use this model in conjunction with a model for heat transfer through walls to model a solar chimney that stores heat.

Dynamics

For a steady-state model, use Buildings.Airflow.Multizone.MediumColumn instead of this model.

In this model, the parameter h must always be positive, and the port port_a must be at the top of the column.

Parameters

TypeNameDefaultDescription
Modelica.Units.SI.Lengthh3Height of shaft
Modelica.Units.SI.VolumeVVolume in medium shaft
Assumptions › Heat transfer
Booleanuse_HeatTransferfalse= true to use the HeatTransfer model

Components

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPort_aport_aFluid connector a (positive design flow direction is from port_a to port_b)
Modelica.Fluid.Interfaces.FluidPort_bport_bFluid connector b (positive design flow direction is from port_a to port_b)
Buildings.Fluid.MixingVolumes.MixingVolumevolAir volume in the shaft
MediumColumncolTopMedium column that connects to top port
MediumColumncolBotMedium colum that connects to bottom port
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_aheatPortHeat port to exchange energy with the fluid volume

Contents

NameDescription
MediumMedium in the component
HeatTransfer

Revisions

  • February 27, 2024, by Michael Wetter:
    Removed wrong annotation that used a non-existent parameter.
    This is for #1842.
  • March 7, 2022, by Michael Wetter:
    Set final massDynamics=energyDynamics.
    This is for #1542.
  • January 18, 2019, by Jianjun Hu:
    Limited the media choice to moist air only. See #1050.
  • January 8, 2019, by Michael Wetter:
    Changed public parameter m_flow_nominal.
    This is for #970.
  • May 1, 2018, by Filip Jorissen:
    Removed declaration of allowFlowReversal and changed default density computation such that it assumes a constant pressure. See #877.
  • October 6, 2014 by Michael Wetter:
    Removed assignment of port_?.p.nominal to avoid a warning in OpenModelica because alias sets have different nominal values.
  • July 31, 2011 by Michael Wetter:
    Changed model to use new base class Buildings.Fluid.Interfaces.LumpedVolumeDeclarations.
  • May 25, 2011 by Michael Wetter:
    Added m_flow_nominal, which is used if component is configured as steady-state.
  • July 28, 2010 by Michael Wetter:
    Released first version.