modelConductionElement
Extends from Internal.PartialConductionElement (Partial model of quasi-stationary mass and heat transfer).
Information
This model represents an element with a fixed volume (fig. 1). The mass inside the volume is assumed quasi-stationary, meaning it is computed statically using the volume and density, and the inlet mass flow is coupled to the outlet mass flow.
Because of this, the ConductionElement cannot be used as a loop breaker.
The advantage of this approach is that multiple ConductionElements can be connected in series without causing oscillations or fast eigenvalues between their masses. The ConductionElement implements conservation of mass and energy equations for the fluid contained within the component.
For further details, see the documentation of the base class Internal.PartialConductionElement.
The useHeatTransferPropertyInput option can be selected to enable input connectors for the overall heat transfer coefficient U or the thermal conductance k = U*A. The resistanceFromAU checkbox determines which quantity is activated:
useHeatTransferPropertyInput = trueandresistanceFromAU = true: enables theUinput (overall heat transfer coefficient)useHeatTransferPropertyInput = trueandresistanceFromAU = false: enables thekinput (thermal conductance)useHeatTransferPropertyInput = falseandresistanceFromAU = true: enables theUparameter (overall heat transfer coefficient)useHeatTransferPropertyInput = falseandresistanceFromAU = false: enables thekparameter (thermal conductance)
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| String | instanceName (from DropOfCommonsPlus) | getInstanceName() | Instance name |
| SI.Volume | V (from PartialConductionElement) | 0.001 | Volume |
| Boolean | displayAnything | displayParameters and (displayVolume or displayConduction) | |
| String | parameterString | if displayParameters and displayVolume and displayConduction then "V=%V, " + conductionString elseif displayParameters and displayVolume and not displayConduction then "V=%V" elseif displayParameters and not displayVolume and displayConduction then conductionString else "" | |
| String | conductionString | if useHeatTransferPropertyInput and resistanceFromAU then "A=%A" elseif not useHeatTransferPropertyInput and resistanceFromAU then "A=%A, U=%U" elseif not useHeatTransferPropertyInput and not resistanceFromAU then "k=%k_par" else "" | |
| 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 |
| Medium.Density | rho_min (from PartialConductionElement) | dropOfCommons.rho_min | Minimal density |
| Boolean | neglectPressureChanges (from PartialConductionElement) | true | =true, if pressure changes are neglected |
| SI.MassFlowRate | m_flow_assert (from PartialConductionElement) | -dropOfCommons.m_flow_reg | Assertion threshold for negative massflows |
| 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 |
| Initialization › Specific enthalpy | |||
| Internal.InitializationMethodsCondElement | init (from PartialConductionElement) | ThermofluidStream.Processes.Internal.InitializationMethodsCondElement.inlet | Initialization for specific enthalpy |
| Medium.Temperature | T_0 (from PartialConductionElement) | Medium.T_default | Initial Temperature |
| Medium.SpecificEnthalpy | h_0 (from PartialConductionElement) | Medium.h_default | Initial specific enthalpy |
| Advanced › Global energy conservation | |||
| Boolean | enforce_global_energy_conservation (from PartialConductionElement) | false | = true, if global conservation of energy is enforced |
| Advanced › global energy conservation | |||
| SI.Time | T_e (from PartialConductionElement) | 100 | Time constant for global conservation of energy |
| Thermal Conductance | |||
| Boolean | useHeatTransferPropertyInput | false | = true, if input connector for either U or k_par is enabled |
| Boolean | resistanceFromAU | true | = true, if thermal conductance is given by U*A |
| SI.Area | A | 1 | Heat transfer area |
| SI.CoefficientOfHeatTransfer | U | 200 | Overall heat transfer coefficient |
| SI.ThermalConductance | k_par | 200 | Thermal conductance |
| Layout › Display parameters | |||
| Boolean | displayVolume | true | = true, if volume V is displayed |
| Boolean | displayConduction | true | = true, if thermal conductance is displayed |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Inlet | inlet (from SISOFlow) | ||
| Outlet | outlet (from SISOFlow) | ||
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heatPort (from PartialConductionElement) | ||
| Modelica.Blocks.Interfaces.RealInput | U_var | Overall heat transfer coefficient input connector [W/(m2.K)] | |
| Modelica.Blocks.Interfaces.RealInput | k_var | Thermal conductance input connector [W/K] |
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 | |
| Medium.SpecificEnthalpy | h (from PartialConductionElement) | Volume? specific enthalpy | |
| Medium.ThermodynamicState | state (from PartialConductionElement) | Medium.setState_phX(p_in, h, Xi_in) | Volume thermodynamic state |
| Medium.Temperature | T (from PartialConductionElement) | Medium.temperature(state) | Volume temperature |
| SI.ThermalConductance | k (from PartialConductionElement) | Thermal conductance | |
| SI.Energy | deltaE_system (from PartialConductionElement) | Energy difference between m_flow*(h_in-h_out) and Q_flow | |
| SI.Mass | M (from PartialConductionElement) | Mass (of the volume) |