modelBasicControlValve
Basic valve model with optional flow characteristics for incompressible fluids
Extends from ThermofluidStream.FlowControl.Internal.PartialValve (Partial implementation of a physical valve).
Information
This model serves for most incompressible applications where basic control valves are needed.
The modeler has the ability to choose between different valve characteristics and flow coefficients.
The three standard curve characteristics (linear, parabolic, equal-percentage) are implemented and can be chosen.
To conclude the parameterization, a flow coefficient has to be set. Most data sheets of valves deliver a corresponding "KVs (CVs)"-Value. Otherwise a nominal mass-flow rate can be set.
For incompressible flow, the reference values for density (1g/cm3) and pressure (1bar) should be unchanged.
Reference values for standardized flow coefficients
When using Kvs, Cvs_US, or
Cvs_UK, the default values
dp_ref = 1 bar and
rho_ref = 1000 kg/m3 must not be modified.
assertionLevel. To test this behavior, a test model has been setup in ValveReferenceValues.Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| String | instanceName (from DropOfCommonsPlus) | getInstanceName() | Instance name |
| Boolean | invertInput (from PartialValve) | false | = true, if input u_in is inverted |
| Boolean | enable_dp_rho_ref (from PartialValve) | Enables/ hides showing dp_ref and rho_ref | |
| Real | k_min (from PartialValve) | 0.03 | Remaining flow at actuation signal u = 0 |
| Layout | |||
| Boolean | displayInstanceName (from DropOfCommonsPlus) | dropOfCommons.displayInstanceNames | = true, if instance name is displayed |
| Boolean | displayParameters (from DropOfCommonsPlus) | dropOfCommons.displayParameters | = true, if displaying parameters is enabled |
| Advanced | |||
| Boolean | considerInertance (from SISOFlow) | dropOfCommons.considerInertance | =true, if transient momentum (inertance) term is considered; disable only for advanced use |
| Utilities.Units.Inertance | L (from SISOFlow) | dropOfCommons.L | Inertance |
| StateSelect | m_flowStateSelect (from SISOFlow) | StateSelect.default | State selection for mass flow rate |
| Boolean | clip_p_out (from SISOFlow) | = false, if dr_corr=0 (correction of inertial pressure difference) | |
| Medium.AbsolutePressure | p_min (from SISOFlow) | dropOfCommons.p_min | Minimum steady-state output pressure |
| AssertionLevel | assertionLevel | AssertionLevel.error | Assertion level for invalid reference values |
| Initialization › Mass flow rate | |||
| InitializationMethods | initM_flow (from SISOFlow) | ThermofluidStream.Utilities.Types.InitializationMethods.none | Initialization method for mass flow rate |
| SI.MassFlowRate | m_flow_0 (from SISOFlow) | 0 | Initial value for mass flow rate |
| Utilities.Units.MassFlowAcceleration | m_acceleration_0 (from SISOFlow) | 0 | Initial value for derivative of mass flow rate |
| Advanced › Reference values | |||
| SI.PressureDifference | dp_ref (from PartialValve) | 1e5 | Reference pressure difference |
| Medium.Density | rho_ref (from PartialValve) | 1000 | Reference density |
| Valve parameters | |||
| FlowCoeffType | flowCoefficient | FlowCoeffType.Kvs | Select type of flow coefficient |
| Real | Kvs | 0 | Kvs-value (metric) from data sheet (valve fully open) |
| Real | Cvs_US | 0 | Cvs-value (US [gal/min]) from data sheet (valve fully open) |
| Real | Cvs_UK | 0 | Cvs-value (UK [gal/min]) from data sheet (valve fully open, deprecated; use Kvs or Cvs_US instead) |
| SI.MassFlowRate | m_flow_ref_set | 0 | Reference mass flow rate |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Inlet | inlet (from SISOFlow) | ||
| Outlet | outlet (from SISOFlow) | ||
| Modelica.Blocks.Interfaces.RealInput | u_in (from PartialValve) | Valve control input signal [] |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.MassFlowRate | m_flow (from SISOFlow) | inlet.m_flow | Mass flow rate |
| SI.Pressure | dr_corr (from SISOFlow) | Correction of inertial pressure difference | |
| SI.Pressure | dp (from SISOFlow) | Pressure difference | |
| Medium.AbsolutePressure | p_in (from SISOFlow) | Medium.pressure(inlet.state) | Inlet pressure |
| Medium.SpecificEnthalpy | h_in (from SISOFlow) | Medium.specificEnthalpy(inlet.state) | Inlet specific enthalpy |
| Medium.MassFraction[Medium.nXi] | Xi_in (from SISOFlow) | Medium.massFraction(inlet.state) | Inlet mass fractions |
| Medium.AbsolutePressure | p_out (from SISOFlow) | Outlet pressure | |
| Medium.SpecificEnthalpy | h_out (from SISOFlow) | Outlet specific enthalpy | |
| Medium.MassFraction[Medium.nXi] | Xi_out (from SISOFlow) | Outlet mass fractions | |
| Real | u (from PartialValve) | Actuation input for flow calculation |
Contents
| Name | Description |
|---|---|
 valveCharacteristics |