modelRealGasJunction_L2
Extends from TransiEnt.Basics.Icons.RealGasJunction_L2 (Icon for real gas junction).
Information
1. Purpose of model
This model represents a junction for real gases. It is a modified version of the model ClaRa.Components.VolumesValvesFittings.Fittings.FlueGasJunction_L2 from ClaRa version 1.3.0. The model is documented there and here only the changes are described.
2. Level of detail, physical effects considered, and physical insight
The two-phase region is deactivated. Pressure losses at the ports have been added. A simplified equation for constant composition can be used to improve simulation speed. Also, a heat port is added with which heat transfer can be integrated. You can choose a quasi-stationary or dynamic mass balance implementations. Additionally, the parameter variableCompositionEntries can be used in case that not all components are freely variable, e.g. when hydrogen is fed into natural gas.
3. Limits of validity
Only valid for real gases without phase change.
4. Interfaces
gasPort1: inlet for gas
gasPort2: inlet for gas
gasPort3: outlet for gas
eye1: outlet
eye2: outlet
heat: heat port
5. Nomenclature
(no elements)
6. Governing Equations
(no remarks)
7. Remarks for Usage
(no remarks)
8. Validation
(no remarks)
9. References
(no remarks)
10. Version History
Created by Christopher Helbig (christopher.helbig@tuhh.de), Nov 2014
Modified by Lisa Andresen (andresen@tuhh.de), Feb 2015
Edited by Carsten Bode (c.bode@tuhh.de), Apr 2016
Revised by Carsten Bode (c.bode@tuhh.de) in Apr 2018 (updated to new ClaRa version 1.3.0)
Modified by Carsten Bode (c.bode@tuhh.de), Feb 2019 (added temperature start value)
Modified by Carsten Bode (c.bode@tuhh.de), Mar 2019 (added pressure losses)
Modified by Carsten Bode (c.bode@tuhh.de), May 2019 (added simplified equation for constant composition)
Modified by Carsten Bode (c.bode@tuhh.de), Sep 2019 (added heat port)
Modified by Carsten Bode (c.bode@tuhh.de), May 2020 (added quasi-stationary equations and simplified equations for only dependent mass fractions)
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer[:] | dependentCompositionEntries | if variableCompositionEntries[1] == 0 then 1:medium.nc else TransiEnt.Basics.Functions.findSetDifference(1:medium.nc, variableCompositionEntries) | Entries of medium vector which are supposed to be dependent on the variable entries |
| Boolean | showData | true | |Summary and Visualisation||True, if a data port containing p,T,h,s,m_flow shall be shown, else false |
| Fundamental Definitions | |||
| TILMedia.VLEFluidTypes.BaseVLEFluid | medium | simCenter.gasModel1 | |
| ClaRa.Basics.Units.Volume | volume | 0.1 | Volume of the junction |
| Boolean | constantComposition | simCenter.useConstCompInGasComp | Use simplified equation for constant composition (xi_nom will be used) |
| SI.MassFraction[medium.nc - 1] | xi_nom | medium.xi_default | Constant composition |
| Integer[:] | variableCompositionEntries | {0} | Entries of medium vector which are supposed to be completely variable |
| Integer | massBalance | 1 | Mass balance and species balance fomulation |
| Boolean | showHeatPort | false | |
| SI.Pressure | p_min_assert | 0 | Minimum pressure in component below which the simulation terminates |
| SI.Pressure | p_max_assert | 1000e5 | Maximum pressure in component above which the simulation terminates |
| Initial Values | |||
| Integer | initOption | 0 | Type of initialisation |
| Boolean | useHomotopy | simCenter.useHomotopy | True, if homotopy method is used during initialisation |
| ClaRa.Basics.Units.Pressure | p_start | simCenter.p_amb_const + simCenter.p_eff_2 | Initial value for gas pressure |
| ClaRa.Basics.Units.EnthalpyMassSpecific | h_start | TILMedia.Internals.VLEFluidConfigurations.FullyMixtureCompatible.VLEFluidFunctions.specificEnthalpy_pTxi(medium, p_start, T_start, xi_start) | Initial value for gas specific enthalpy |
| ClaRa.Basics.Units.MassFraction | xi_start | medium.xi_default | Initial value for mass fractions |
| ClaRa.Basics.Units.Temperature | T_start | simCenter.T_ground | Initial value for gas temperature (used in calculation of h_start) |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| TransiEnt.Basics.Interfaces.Gas.RealGasPortIn | gasPort1 | ||
| TransiEnt.Basics.Interfaces.Gas.RealGasPortIn | gasPort2 | ||
| TransiEnt.Basics.Interfaces.Gas.RealGasPortOut | gasPort3 | ||
| ClaRa.Basics.Interfaces.EyeOut | eye1 | ||
| ClaRa.Basics.Interfaces.EyeOut | eye2 | ||
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heat |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| TransiEnt.SimCenter | simCenter | ||
| PressureLoss1 | pressureLoss1 | ||
| PressureLoss2 | pressureLoss2 | ||
| PressureLoss3 | pressureLoss3 | ||
| ClaRa.Basics.Units.MassFraction[medium.nc - 1] | xi | ||
| Modelica.Units.SI.MassFraction | xi_end | 1 - sum(xi) | Last entry of mass fraction |
| Modelica.Units.SI.SpecificEnthalpy | h | Specific enthalpy | |
| ClaRa.Basics.Units.Pressure | p | ||
| ClaRa.Basics.Units.Mass | mass | Gas mass in control volume | |
| Summary | summary |
Contents
| Name | Description |
|---|---|
 Summaryprotected | |
 PressureLoss1 | |
| PressureLoss2 | |
| PressureLoss3 |