modelMassFlowRateMultiplier

Model that multiplies the mass flow rate

Extends from Buildings.Fluid.Interfaces.PartialTwoPort (Partial component with two ports).

Information

This model multiplies the mass flow rate so that 0 = port_b.m_flow + gain * port_a.m_flow where gain > 0 is either equal to the input variable u if use_input is set to true, or equal to the parameter k if use_input is set to false.

The specific enthalpy, the species concentration and the trace substance concentration remain unchanged. Therefore, this model does not conserve mass or energy. It is used in Buildings.Fluid.Geothermal.Borefields.BaseClasses.PartialBorefield and also in the Buildings library to avoid having to instantiate circuits in parallel, with each having the same mass flow rate and temperatures.

Parameters

TypeNameDefaultDescription
Booleanuse_inputfalseSet to true for multiplier factor provided as an input instead of a parameter
Realk1Gain for mass flow rate
Assumptions
BooleanallowFlowReversal (from PartialTwoPort)true= false to simplify equations, assuming, but not enforcing, no flow reversal

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)
Modelica.Blocks.Interfaces.RealInputuMultiplier factor
Modelica.Blocks.Interfaces.RealOutputuInvInverse of the multiplier factor

Revisions

  • January 11, 2023, by Antoine Gautier:
    Added option to use input connector as multiplier factor.
    This is for #1684.
  • March 27, 2013, by Michael Wetter:
    Changed implementation to extend from Modelica.Fluid.
  • June 27, 2012, by Michael Wetter:
    First implementation.