.BuildSysPro.IBPSA.Airflow.Multizone.BaseClasses.TwoWayFlowElement

Information

This is a partial model for models that describe the bi-directional air flow through large openings.

Models that extend this model need to compute mAB_flow and mBA_flow, or alternatively VAB_flow and VBA_flow, and the face area area. The face area is a variable to allow this partial model to be used for doors that can be open or closed as a function of an input signal.

Contents

Name	Description
Medium	Medium in the component

Revisions

• May 12, 2020, by Michael Wetter:
  Changed assignment of m1_flow_small and m2_flow_small to final. These quantities are not used in this model and models that extend from it. Hence there is no need for the user to change the value.
• January 18, 2019, by Jianjun Hu:
  Limited the media choice to moist air only. See #1050.
• September 13, 2018, by Michael Wetter:
  Set allowFlowReversal=true as the flow can be slightly negative due to the regularization, in which case the m_flow(min=0) that is set in the base class IBPSA.Fluid.Interfaces.PartialFourPort is violated.
  See #937.
• November 3, 2016, by Michael Wetter:
  Removed start values for inflowing density to simplify the parameter window, and because this can usually be computed from the state variables.
  This is for #552.
• February 24, 2015 by Michael Wetter:
  Changed model to use Buildings.Utilities.Psychrometrics.Functions.density_pTX for the density computation as Buildings.Media.Air.density does not depend on temperature.
• June 18, 2014 by Michael Wetter:
  Added start values and fixed=true attribute for mExcAB and mExcBA. This avoids a warning during translation.
• July 20, 2010 by Michael Wetter:
  Migrated model to Modelica 3.1 and integrated it into the Buildings library.
• February 4, 2005 by Michael Wetter:
  Released first version.