modelMassFlowSource_h

Ideal flow source that produces a prescribed mass flow with prescribed specific enthalpy, composition and trace substances

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Extends from Buildings.Fluid.Sources.BaseClasses.PartialSource_Xi_C (Partial component source with parameter definitions for Xi and C).

Information

Models an ideal flow source, with prescribed values of flow rate, specific enthalpy, composition and trace substances:

Prescribed mass flow rate.
Prescribed specific enthalpy.
Boundary composition (only for multi-substance or trace-substance flow).

If use_m_flow_in is false (default option), the m_flow parameter is used as boundary pressure, and the m_flow_in input connector is disabled; if use_m_flow_in is true, then the m_flow parameter is ignored, and the value provided by the input connector is used instead.

The same applies to the specific enthalpy h, composition X_i or X and trace substances C.

Options

Instead of using Xi_in (the independent composition fractions), the advanced tab provides an option for setting all composition fractions using X_in. use_X_in and use_Xi_in cannot be used at the same time.

Parameter verifyInputs can be set to true to enable a check that verifies the validity of the used specific enthalpy and pressures. This removes the corresponding overhead from the model, which is a substantial part of the overhead of this model. See #882 for more information.

Note, that boundary specific enthalpy, mass fractions and trace substances have only an effect if the mass flow is from the boundary into the port. If mass is flowing from the port into the boundary, the boundary definitions, with exception of boundary flow rate, do not have an effect.

Parameters

Type	Name	Default	Description
Integer	nPorts (from PartialSource)	0	Number of ports
Advanced
Boolean	verifyInputs (from PartialSource)	false	Set to true to stop the simulation with an error if the medium temperature is outside its allowable range
Boolean	use_X_in (from PartialSource_Xi_C)	false	Get the composition (all fractions) from the input connector
Conditional inputs
Boolean	use_Xi_in (from PartialSource_Xi_C)	false	Get the composition (independent fractions) from the input connector
Boolean	use_C_in (from PartialSource_Xi_C)	false	Get the trace substances from the input connector
Boolean	use_m_flow_in	false	Get the mass flow rate from the input connector
Boolean	use_h_in	false	Get the specific enthalpy from the input connector
Fixed inputs
Medium.MassFraction[Medium.nX]	X (from PartialSource_Xi_C)	Medium.X_default	Fixed value of composition
Medium.ExtraProperty[Medium.nC]	C (from PartialSource_Xi_C)	fill(0, Medium.nC)	Fixed values of trace substances
Modelica.Units.SI.MassFlowRate	m_flow	0	Fixed mass flow rate going out of the fluid port
Medium.SpecificEnthalpy	h	Medium.h_default	Fixed value of specific enthalpy

Connectors

Type	Name	Description
Modelica.Fluid.Interfaces.FluidPorts_b[nPorts]	ports (from PartialSource)	Fluid ports
Modelica.Blocks.Interfaces.RealInput[Medium.nX]	X_in (from PartialSource_Xi_C)	Prescribed boundary composition
Modelica.Blocks.Interfaces.RealInput[Medium.nXi]	Xi_in (from PartialSource_Xi_C)	Prescribed boundary composition
Modelica.Blocks.Interfaces.RealInput[Medium.nC]	C_in (from PartialSource_Xi_C)	Prescribed boundary trace substances
Modelica.Blocks.Interfaces.RealInput	m_flow_in	Prescribed mass flow rate
Modelica.Blocks.Interfaces.RealInput	h_in	Prescribed boundary specific enthalpy

Revisions

March 11, 2024, by Michael Wetter:
Corrected use of HideResult.
This is for #1850.
February 2nd, 2018 by Filip Jorissen
Made medium conditional and refactored inputs. See #882.
April 18, 2017, by Filip Jorissen:
Changed checkBoundary implementation such that it is run as an initial equation when it depends on parameters only. See #728.
January 26, 2016, by Michael Wetter:
Added unit and quantity attributes.
May 29, 2014, by Michael Wetter:
Removed undesirable annotation Evaluate=true.
September 29, 2009, by Michael Wetter:
First implementation. Implemenation is based on Modelica.Fluid.