modelPartialDynamicFlowSensor

Partial component to model sensors that measure flow properties using a dynamic model

Extends from PartialFlowSensor (Partial component to model sensors that measure flow properties).

Information

Partial component to model a sensor that measures any intensive properties of a flow, e.g., to get temperature or density in the flow between fluid connectors.

The sensor computes a gain that is zero at zero mass flow rate. This avoids fast transients if the flow is close to zero, thereby improving the numerical efficiency.

Parameters

TypeNameDefaultDescription
Modelica.SIunits.Timetau1Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems)
Assumptions
BooleanallowFlowReversal (from PartialTwoPort)true= false to simplify equations, assuming, but not enforcing, no flow reversal
Nominal condition
Modelica.SIunits.MassFlowRatem_flow_nominal (from PartialFlowSensor)Nominal mass flow rate, used for regularization near zero flow
Advanced
Modelica.SIunits.MassFlowRatem_flow_small (from PartialFlowSensor)1E-4*m_flow_nominalFor bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required)
Initialization
Modelica.Blocks.Types.InitinitTypeModelica.Blocks.Types.Init.InitialStateType of initialization (InitialState and InitialOutput are identical)

Connectors

TypeNameDefaultDescription
Modelica.Fluid.Interfaces.FluidPort_aport_a (from PartialTwoPort)Fluid connector a (positive design flow direction is from port_a to port_b)
Modelica.Fluid.Interfaces.FluidPort_bport_b (from PartialTwoPort)Fluid connector b (positive design flow direction is from port_a to port_b)

Revisions

  • August 9, 2016, by Michael Wetter:
    Improved documentation for tau.
  • January 12, 2016, by Filip Jorissen:
    Added optional parameter tauInv.
  • May 29, 2014, by Michael Wetter:
    Removed undesirable annotation Evaluate=true.
  • March 29, 2013, by Michael Wetter:
    Changed the parameter initType to Modelica.Blocks.Types.Init.InitialState. This allows a pedantic model check in Dymola 2014 of models that instanciate sensors but do not set this parameter. It also ensures that different Modelica simulators solve the same initialization problem.
  • July 7, 2011, by Michael Wetter:
    First implementation.