.BuildSysPro.IBPSA.Fluid.BaseClasses.PartialThreeWayResistance

Information

Partial model for flow resistances with three ports such as a flow mixer/splitter or a three way valve.

If energyDynamics ≠ Modelica.Fluid.Types.Dynamics.SteadyState, then at the junction of the three flows, a mixing volume will be present. This will introduce a dynamic energy and momentum balance, which often breaks algebraic loops. The time constant of the mixing volume is determined by the parameter tau.

Revisions

• March 7, 2022, by Michael Wetter:
  Set final massDynamics=energyDynamics.
  This is for #1542.
• March 22, 2020, by Filip Jorissen:
  Corrected error message of asserts that verify whether flow reversal occurs when verifyFlowReversal=true and portFlowDirection<>Bidirectional. See #1327.
• July 7, 2018, by Filip Jorissen:
  Added asserts that verify whether flow reversal occurs when verifyFlowReversal=true and portFlowDirection<>Bidirectional. See #963.
• July 8, 2018, by Filip Jorissen:
  Added nominal value of h_outflow in FluidPorts. See #977.
• March 30, 2018, by Filip Jorissen:
  Added graphical illustrations for the values of portFlowDirection. Added asserts that verify the consistency of the values of portFlowDirection. See #902.
• February 22, 2016, by Michael Wetter:
  Conditionally removed control volume vol, and added the conditional connnector port_internal. This was already done when the parameter dynamicBalance was present, but was updated wrong when this parameter was removed. Without these conditional components, the regression test for IBPSA.Fluid.Examples.ResistanceVolumeFlowReversal fails to simulate.
• December 17, 2015, by Michael Wetter:
  Added assignment redeclare final package Medium=Medium as this is required for OpenModelica. This is for https://github.com/lbl-srg/modelica-buildings/issues/475.
• February 20, 2016, by Ruben Baetens:
  Removal of dynamicBalance as parameter for massDynamics and energyDynamics.
• April 13 2015, by Filip Jorissen:
  Exposed options for flow reversal to users and added corresponding implementation.
• March 23 2010, by Michael Wetter:
  Changed start values from system.p_start or (code T_start) to Medium.p_default.
• September 18, 2008 by Michael Wetter:
  Replaced splitter model with a fluid port since the splitter model in Modelica.Fluid 1.0 beta does not transport mC_flow.
• June 11, 2008 by Michael Wetter:
  First implementation.