.BuildSysPro.IBPSA.Fluid.Sensors.LatentEnthalpyFlowRate

Information

This model outputs the latent enthalphy flow rate of the medium in the flow between its fluid ports. In particular, if the total enthalpy flow rate is

Ḣ_tot = Ḣ_sen + Ḣ_lat,

where Ḣ_sen = ṁ (1-X_w) c_p,air, then this sensor outputs Ḣ = Ḣ_lat.

If the parameter tau is non-zero, then the measured specific latent enthalpy h_out that is used to compute the latent enthalpy flow rate Ḣ_lat = ṁ h_out is computed using a first order differential equation. See IBPSA.Fluid.Sensors.UsersGuide for an explanation.

For a sensor that measures Ḣ_tot, use IBPSA.Fluid.Sensors.EnthalpyFlowRate.
For a sensor that measures Ḣ_sen, use IBPSA.Fluid.Sensors.SensibleEnthalpyFlowRate.

The sensor is ideal, i.e., it does not influence the fluid. The sensor can only be used with medium models that implement the function enthalpyOfNonCondensingGas(T).

Revisions

• October 19, 2020, by Antoine Gautier:
  Changed default value for tau from 1 to 0.
  This is for #1406.
• February 25, 2020, by Michael Wetter:
  Changed icon to display its operating state.
  This is for #1294.
• January 18, 2016 by Filip Jorissen:
  Using parameter tauInv since this now exists in IBPSA.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor. This is for #372.
• September 10, 2013, by Michael Wetter:
  Changed medium declaration in the extends statement to replaceable to avoid a translation error in OpenModelica.
• August 31, 2013, by Michael Wetter:
  Removed default value tau=0 as the base class already sets tau=1. This change was made so that all sensors use the same default value.
• December 18, 2012, by Michael Wetter:
  Moved computation of i_w to new base class IBPSA.Fluid.BaseClasses.IndexWater. The value of this parameter is now assigned dynamically and does not require to be specified by the user.
• November 3, 2011, by Michael Wetter:
  Moved der(h_out) := 0; from the initial algorithm section to the initial equation section as this assignment does not conform to the Modelica specification.
• August 10, 2011 by Michael Wetter:
  Added parameter i_w and an assert statement to make sure it is set correctly. Without this change, Dymola cannot differentiate the model when reducing the index of the DAE.
• June 3, 2011 by Michael Wetter:
  Revised implementation to add dynamics in such a way that the time constant increases as the mass flow rate tends to zero. This can improve the numerics.
• February 22, by Michael Wetter:
  Improved code that searches for index of 'water' in medium model.
• September 9, 2009 by Michael Wetter:
  First implementation. Implementation is based on enthalpy sensor of Modelica.Fluid.