Buildings.Fluid.Sensors
Package with sensor models
Information
Package Sensors
consists of idealized sensor components that
provide variables of a medium as
output signals. These signals can be, e.g., further processed
with components of the
Modelica.Blocks
library.
Extends from Modelica.Icons.SensorsPackage (Icon for packages containing sensors).
Package Content
Name | Description |
---|---|
UsersGuide | User's Guide |
Density | Ideal one port density sensor |
DensityTwoPort | Ideal two port density sensor |
EnthalpyFlowRate | Ideal enthalphy flow rate sensor |
EntropyFlowRate | Ideal entropy flow rate sensor |
LatentEnthalpyFlowRate | Ideal enthalphy flow rate sensor that outputs the latent enthalpy flow rate only |
MassFlowRate | Ideal sensor for mass flow rate |
MassFraction | Ideal one port mass fraction sensor |
MassFractionTwoPort | Ideal two port mass fraction sensor |
PPM | Ideal one port trace substances sensor outputting in parts per million |
PPMTwoPort | Ideal two port trace substances sensor outputting in parts per million |
Pressure | Ideal pressure sensor |
RelativeHumidity | Ideal one port relative humidity sensor |
RelativeHumidityTwoPort | Ideal two port relative humidity sensor |
RelativePressure | Ideal relative pressure sensor |
RelativeTemperature | Ideal relative temperature sensor |
SensibleEnthalpyFlowRate | Ideal enthalphy flow rate sensor that outputs the sensible enthalpy flow rate only |
SpecificEnthalpy | Ideal one port specific enthalpy sensor |
SpecificEnthalpyTwoPort | Ideal two port sensor for the specific enthalpy |
SpecificEntropy | Ideal one port specific entropy sensor |
SpecificEntropyTwoPort | Ideal two port sensor for the specific entropy |
Temperature | Ideal one port temperature sensor |
TemperatureTwoPort | Ideal two port temperature sensor |
TemperatureWetBulbTwoPort | Ideal wet bulb temperature sensor |
TraceSubstances | Ideal one port trace substances sensor |
TraceSubstancesTwoPort | Ideal two port sensor for trace substance |
Velocity | Ideal sensor for flow velocity |
VolumeFlowRate | Ideal sensor for volume flow rate |
Conversions | Package with conversions for sensor models |
Examples | Collection of models that illustrate model use and test models |
BaseClasses | Package with base classes for Buildings.Fluid.Sensors |
Buildings.Fluid.Sensors.Density
Ideal one port density sensor
Information
This model outputs the density of the fluid connected to its port. The sensor is ideal, i.e. it does not influence the fluid.
To measure density in a duct or pipe, use Buildings.Fluid.Sensors.DensityTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | d | Density in port medium [kg/m3] |
Modelica definition
Buildings.Fluid.Sensors.DensityTwoPort
Ideal two port density sensor
Information
This model outputs the density of the fluid flowing from
port_a
to port_b
.
The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Density | d_start | Medium.density(state=Medium.... | Initial or guess value of output (=state) [kg/m3] |
Temperature | T_start | Medium.T_default | Temperature used to compute d_start [K] |
Pressure | p_start | Medium.p_default | Pressure used to compute d_start [Pa] |
MassFraction | X_start[Medium.nX] | Medium.X_default | Mass fraction used to compute d_start [1] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | d | Density of the passing fluid [kg/m3] |
Modelica definition
Buildings.Fluid.Sensors.EnthalpyFlowRate
Ideal enthalphy flow rate sensor
Information
This model outputs the enthalphy flow rate of the medium in the flow between fluid ports. The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then the measured
specific enthalpy hout that is used to
compute the enthalpy flow rate
Ḣ = ṁ hout
is computed using a first order differential equation.
See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
For a sensor that measures the latent enthalpy flow rate, use Buildings.Fluid.Sensors.LatentEnthalpyFlowRate.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 0 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
SpecificEnthalpy | h_out_start | Medium.specificEnthalpy_pTX(... | Initial or guess value of measured specific enthalpy [J/kg] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | H_flow | Enthalpy flow rate, positive if from port_a to port_b [W] |
Modelica definition
Buildings.Fluid.Sensors.EntropyFlowRate
Ideal entropy flow rate sensor
Information
This model outputs the entropy flow rate of the medium in the flow between fluid ports. The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then the measured
specific entropy sout that is used to
compute the entropy flow rate
Ṡ = ṁ sout
is computed using a first order differential equation.
See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 0 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
SpecificEntropy | s_out_start | Medium.specificEntropy_pTX(p... | Initial or guess value of measured specific entropy [J/(kg.K)] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | S_flow | Entropy flow rate, positive if from port_a to port_b [W/K] |
Modelica definition
Buildings.Fluid.Sensors.LatentEnthalpyFlowRate
Ideal enthalphy flow rate sensor that outputs the latent enthalpy flow rate only
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
Ḣtot = Ḣsen + Ḣlat,
where Ḣsen = ṁ (1-Xw) cp,air, then this sensor outputs Ḣ = Ḣlat.
If the parameter tau
is non-zero, then the measured
specific latent enthalpy hout that is used to
compute the latent enthalpy flow rate
Ḣlat = ṁ hout
is computed using a first order differential equation.
See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
For a sensor that measures
Ḣtot, use
Buildings.Fluid.Sensors.EnthalpyFlowRate.
For a sensor that measures
Ḣsen, use
Buildings.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)
.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Buildings.Fluid.BaseClasses.IndexMassFraction (Computes the index of a substance in the mass fraction vector Xi), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 0 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
String | substanceName | "water" | Name of species substance |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
SpecificEnthalpy | h_out_start | Medium.specificEnthalpy_pTX(... | Initial or guess value of measured specific latent enthalpy [J/kg] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium in the component | |
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | H_flow | Latent enthalpy flow rate, positive if from port_a to port_b [W] |
Modelica definition
Buildings.Fluid.Sensors.MassFlowRate
Ideal sensor for mass flow rate
Information
This model outputs the mass flow rate flowing from
port_a
to port_b
.
The sensor is ideal, i.e., it does not influence the fluid.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialFlowSensor (Partial component to model sensors that measure flow properties), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Nominal condition | |||
MassFlowRate | m_flow_nominal | 0 | Nominal mass flow rate, used for regularization near zero flow [kg/s] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 0 | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | m_flow | Mass flow rate from port_a to port_b [kg/s] |
Modelica definition
Buildings.Fluid.Sensors.MassFraction
Ideal one port mass fraction sensor
Information
This model outputs the mass fraction of the fluid connected to its port. The sensor is ideal, i.e., it does not influence the fluid.
To measure mass fraction in a duct or pipe, use Buildings.Fluid.Sensors.MassFractionTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Buildings.Fluid.BaseClasses.IndexMassFraction (Computes the index of a substance in the mass fraction vector Xi), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
String | substanceName | "water" | Name of species substance |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium in the sensor | |
FluidPort_a | port | |
output RealOutput | X | Mass fraction in port [kg/kg] |
Modelica definition
Buildings.Fluid.Sensors.MassFractionTwoPort
Ideal two port mass fraction sensor
Information
This model outputs the mass fraction of the passing fluid.
The sensor is ideal, i.e. it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Buildings.Fluid.BaseClasses.IndexMassFraction (Computes the index of a substance in the mass fraction vector Xi), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
String | substanceName | "water" | Name of species substance |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
MassFraction | X_start | Medium.X_default[i_x] | Initial or guess value of output (= state) [kg/kg] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium in the component | |
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | X | Mass fraction of the passing fluid [kg/kg] |
Modelica definition
Buildings.Fluid.Sensors.PPM
Ideal one port trace substances sensor outputting in parts per million
Information
This model outputs the trace substance concentration in ppm contained in the fluid connected to its port. The sensor is ideal, i.e., it does not influence the fluid.
The parameter MM
is the molar mass of the trace substance.
For a list of molar masses, see
Modelica.Media.IdealGases.Common.SingleGasesData
and
Modelica.Media.IdealGases.Common.FluidData.
To measure PPM in a duct or pipe, use Buildings.Fluid.Sensors.PPMTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Assumptions
This sensor assumes that the concentration C of the medium is in mass fraction. Otherwise, the conversion to ppm will be wrong.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
String | substanceName | "CO2" | Name of trace substance |
MolarMass | MM | Modelica.Media.IdealGases.Co... | Molar mass of the trace substance [kg/mol] |
Connectors
Type | Name | Description |
---|---|---|
output RealOutput | ppm | Trace substance in port medium in ppm |
Modelica definition
Buildings.Fluid.Sensors.PPMTwoPort
Ideal two port trace substances sensor outputting in parts per million
Information
This model outputs the trace substance of the passing fluid
in parts per million.
The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
String | substanceName | "CO2" | Name of trace substance |
MolarMass | MM | Modelica.Media.IdealGases.Co... | Molar mass of the trace substance [kg/mol] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Real | C_start | 0 | Initial or guess value of output (= state) |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
output RealOutput | ppm | Trace substance in port medium in ppm |
Modelica definition
Buildings.Fluid.Sensors.Pressure
Ideal pressure sensor
Information
This model outputs the absolute pressure of the fluid connected to its port. The sensor is ideal, i.e., it does not influence the fluid.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | false | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | p | Pressure at port [Pa] |
Modelica definition
Buildings.Fluid.Sensors.RelativeHumidity
Ideal one port relative humidity sensor
Information
This model outputs the relative humidity of the fluid connected to its port. The sensor is ideal, i.e. it does not influence the fluid.
Note that this sensor can only be used with media that contain the variable phi
,
which is typically the case for moist air models.
To measure relative humidity in a duct or pipe, use Buildings.Fluid.Sensors.RelativeHumidityTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | phi | Relative humidity in port medium [1] |
Modelica definition
Buildings.Fluid.Sensors.RelativeHumidityTwoPort
Ideal two port relative humidity sensor
Information
This model outputs the relative humidity of the fluid flowing from
port_a
to port_b
.
The sensor is ideal, i.e., it does not influence the fluid.
Note that this sensor can only be used with media that contain the variable phi
,
which is typically the case for moist air models.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Real | phi_start | 0.5 | Initial or guess value of output (= state) [1] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | phi | Relative humidity of the passing fluid [1] |
Modelica definition
Buildings.Fluid.Sensors.RelativePressure
Ideal relative pressure sensor
Information
The relative pressure port_a.p - port_b.p
is determined between
the two ports of this component and is provided as output signal. The
sensor should be connected in parallel with other equipment, no flow
through the sensor is allowed.
Extends from Modelica.Icons.TranslationalSensor (Icon representing a linear measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium in the sensor |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium in the sensor | |
FluidPort_a | port_a | Fluid connector of stream a |
FluidPort_b | port_b | Fluid connector of stream b |
output RealOutput | p_rel | Relative pressure of port_a minus port_b [Pa] |
Modelica definition
Buildings.Fluid.Sensors.RelativeTemperature
Ideal relative temperature sensor
Information
The relative temperature T(port_a) - T(port_b)
is determined between
the two ports of this component and is provided as output signal. The
sensor should be connected in parallel with other equipment.
There is no flow through the sensor.
Note that this sensor should only be connected to fluid volumes, such as Buildings.Fluid.MixingVolumes.MixingVolume. Otherwise, numerical problems may occur if one of the mass flow rates are close to zero. See Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Modelica.Icons.TranslationalSensor (Icon representing a linear measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium in the sensor |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium in the sensor | |
FluidPort_a | port_a | Fluid connector of stream a |
FluidPort_b | port_b | Fluid connector of stream b |
output RealOutput | T_rel | Temperature difference of port_a minus port_b [K] |
Modelica definition
Buildings.Fluid.Sensors.SensibleEnthalpyFlowRate
Ideal enthalphy flow rate sensor that outputs the sensible enthalpy flow rate only
Information
This model outputs the sensible enthalphy flow rate of the medium in the flow between its fluid ports. In particular, if the total enthalpy flow rate is
Ḣtot = Ḣsen + Ḣlat,
where Ḣsen = ṁ (1-Xw) cp,air, then this sensor outputs Ḣ = Ḣsen.
If the parameter tau
is non-zero, then the measured
specific sensible enthalpy hout that is used to
compute the sensible enthalpy flow rate
Ḣsen = ṁ hout
is computed using a first order differential equation.
See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
For a sensor that measures
Ḣtot, use
Buildings.Fluid.Sensors.EnthalpyFlowRate.
For a sensor that measures
Ḣlat, use
Buildings.Fluid.Sensors.LatentEnthalpyFlowRate.
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)
.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Buildings.Fluid.BaseClasses.IndexMassFraction (Computes the index of a substance in the mass fraction vector Xi), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 0 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
String | substanceName | "water" | Name of species substance |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
SpecificEnthalpy | h_out_start | Medium.enthalpyOfNonCondensi... | Initial or guess value of measured specific sensible enthalpy [J/kg] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
replaceable package Medium | Medium in the component | |
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | H_flow | Sensible enthalpy flow rate, positive if from port_a to port_b [W] |
Modelica definition
Buildings.Fluid.Sensors.SpecificEnthalpy
Ideal one port specific enthalpy sensor
Information
This model outputs the specific enthalpy of the fluid connected to its port. The sensor is ideal, i.e. it does not influence the fluid.
To measure specific enthalpy in a duct or pipe, use Buildings.Fluid.Sensors.SpecificEnthalpyTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | h_out | Specific enthalpy in port medium [J/kg] |
Modelica definition
Buildings.Fluid.Sensors.SpecificEnthalpyTwoPort
Ideal two port sensor for the specific enthalpy
Information
This model outputs the specific enthalpy of a passing fluid.
The sensor is ideal, i.e. it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
SpecificEnthalpy | h_out_start | Medium.specificEnthalpy_pTX(... | Initial or guess value of output (= state) [J/kg] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | h_out | Specific enthalpy of the passing fluid [J/kg] |
Modelica definition
Buildings.Fluid.Sensors.SpecificEntropy
Ideal one port specific entropy sensor
Information
This model outputs the specific entropy of the fluid connected to its port. The sensor is ideal, i.e., it does not influence the fluid.
To measure specific entropy in a duct or pipe, use Buildings.Fluid.Sensors.SpecificEntropyTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | s | Specific entropy in port medium [J/(kg.K)] |
Modelica definition
Buildings.Fluid.Sensors.SpecificEntropyTwoPort
Ideal two port sensor for the specific entropy
Information
This model outputs the specific entropy of the passing fluid.
The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
SpecificEntropy | s_start | Medium.specificEntropy_pTX(p... | Initial or guess value of output (= state) [J/(kg.K)] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | s | Specific entropy of the passing fluid [J/(kg.K)] |
Modelica definition
Buildings.Fluid.Sensors.Temperature
Ideal one port temperature sensor
Information
This model outputs the temperature of the fluid connected to its port. The sensor is ideal, i.e., it does not influence the fluid.
To measure temperature in a duct or pipe, use Buildings.Fluid.Sensors.TemperatureTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | T | Temperature in port medium [K] |
Modelica definition
Buildings.Fluid.Sensors.TemperatureTwoPort
Ideal two port temperature sensor
Information
This model outputs the temperature of the medium in the flow between its fluid ports. The sensor does not influence the fluid.
Typical use and important parameters
If the parameter tau
is non-zero, then its output T
converges to the temperature of the incoming fluid using
a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
If transferHeat = true
, then heat transfer with the ambient is
approximated and T converges towards the fixed ambient
temperature TAmb using a first order approximation
with a time constant of tauHeaTra
when the flow rate is small.
Note that no energy is exchanged with the fluid as the
sensor does not influence the fluid temperature.
Setting transferHeat = true
is useful, for example,
if the sensor is used to measure the fluid temperature in
a system with on/off control on the mass flow rate.
If transferHeat
were false
, then the sensor output T
would remain constant if the mass flow rate is set to zero, and hence
the controller may never switch the mass flow rate on again.
In general, applications in which the sensor output is not used to switch
the mass flow rate on should set transferHeat=false
.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Temperature | T_start | Medium.T_default | Initial or guess value of output (= state) [K] |
Heat transfer | |||
Boolean | transferHeat | false | if true, temperature T converges towards TAmb when no flow |
Temperature | TAmb | Medium.T_default | Fixed ambient temperature for heat transfer [K] |
Time | tauHeaTra | 1200 | Time constant for heat transfer, default 20 minutes [s] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | T | Temperature of the passing fluid [K] |
Modelica definition
Buildings.Fluid.Sensors.TemperatureWetBulbTwoPort
Ideal wet bulb temperature sensor
Information
This sensor outputs the wet bulb temperature of the medium in the flow
between its fluid ports. The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Temperature | TWetBul_start | Medium.T_default | Initial or guess value of wet bulb temperature (used to compute initial output signal)) [K] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | T | Wet bulb temperature in port medium [K] |
Modelica definition
Buildings.Fluid.Sensors.TraceSubstances
Ideal one port trace substances sensor
Information
This model outputs the trace substances contained in the fluid connected to its port. The sensor is ideal, i.e., it does not influence the fluid.
To measure trace substances in a duct or pipe, use Buildings.Fluid.Sensors.TraceSubstancesTwoPort rather than this sensor. Read the Buildings.Fluid.Sensors.UsersGuide prior to using this model to see about potential numerical problems if this sensor is used incorrectly in a system model.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialAbsoluteSensor (Partial component to model a sensor that measures a potential variable), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the sensor | |
Boolean | warnAboutOnePortConnection | true | Set to false to suppress warning about potential numerical issues, see Buildings.Fluid.Sensors.UsersGuide for more information |
String | substanceName | "CO2" | Name of trace substance |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port | |
output RealOutput | C | Trace substance in port medium |
Modelica definition
Buildings.Fluid.Sensors.TraceSubstancesTwoPort
Ideal two port sensor for trace substance
Information
This model outputs the trace substance of the passing fluid.
The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then its output
is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
String | substanceName | "CO2" | Name of trace substance |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Real | C_start | 0 | Initial or guess value of output (= state) |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | C | Trace substance of the passing fluid |
Modelica definition
Buildings.Fluid.Sensors.Velocity
Ideal sensor for flow velocity
Information
This model outputs the flow velocity flowing from
port_a
to port_b
.
The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then the measured
density that is used to convert the mass flow rate into
volumetric flow rate is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Typical use and important parameters
In order to use the flow velocity sensor, the cross sectional area of the flow
channel crossSection
must be specified in m2
. For a
circular flow channel (e.g. a round pipe) of diameter diameter
, the
cross sectional area can be specified as crossSection = diameter *
diameter / 4 * Modelica.Constants.pi
. See
Buildings.Fluid.Sensors.Examples.Velocity for an example implementation
with diameter = 0.1
.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 1 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Area | A | Cross sectional area of flow channel [m2] | |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Density | d_start | Medium.density(Medium.setSta... | Initial or guess value of density [kg/m3] |
Temperature | T_start | Medium.T_default | Temperature used to compute d_start [K] |
Pressure | p_start | Medium.p_default | Pressure used to compute d_start [Pa] |
MassFraction | X_start[Medium.nX] | Medium.X_default | Mass fraction used to compute d_start [1] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | v | Flow velocity from port_a to port_b [m/s] |
Modelica definition
Buildings.Fluid.Sensors.VolumeFlowRate
Ideal sensor for volume flow rate
Information
This model outputs the volume flow rate flowing from
port_a
to port_b
.
The sensor is ideal, i.e., it does not influence the fluid.
If the parameter tau
is non-zero, then the measured
density that is used to convert the mass flow rate into
volumetric flow rate is computed using a first order differential equation.
Setting tau=0
is not recommend. See
Buildings.Fluid.Sensors.UsersGuide for an explanation.
Extends from Buildings.Fluid.Sensors.BaseClasses.PartialDynamicFlowSensor (Partial component to model sensors that measure flow properties using a dynamic model), Modelica.Icons.RotationalSensor (Icon representing a round measurement device).
Parameters
Type | Name | Default | Description |
---|---|---|---|
replaceable package Medium | PartialMedium | Medium in the component | |
Time | tau | 0 | Time constant at nominal flow rate (use tau=0 for steady-state sensor, but see user guide for potential problems) [s] |
Nominal condition | |||
MassFlowRate | m_flow_nominal | Nominal mass flow rate, used for regularization near zero flow [kg/s] | |
Initialization | |||
Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization (InitialState and InitialOutput are identical) |
Density | d_start | Medium.density(Medium.setSta... | Initial or guess value of density [kg/m3] |
Temperature | T_start | Medium.T_default | Temperature used to compute d_start [K] |
Pressure | p_start | Medium.p_default | Pressure used to compute d_start [Pa] |
MassFraction | X_start[Medium.nX] | Medium.X_default | Mass fraction used to compute d_start [1] |
Assumptions | |||
Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
Advanced | |||
MassFlowRate | m_flow_small | 1E-4*m_flow_nominal | For bi-directional flow, temperature is regularized in the region |m_flow| < m_flow_small (m_flow_small > 0 required) [kg/s] |
Connectors
Type | Name | Description |
---|---|---|
FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
output RealOutput | V_flow | Volume flow rate from port_a to port_b [m3/s] |