FlueGasJunction L2
Created Monday 24 March 2014
Adiabatic 3-port flue gas junction model describing a gas volume with dynamic energy and mass balance neglecting pressure losses.
1. Purpose of Model
The model is used as mixing or splitting component with a constant volume which handle gaseous media.
2. Level of Detail, Physical Effects Considered and Physical Insight
2.1 Level of Detail
Referring to Brunnemann et al. [1], this model refers to the level of detail L2.
2.2 Physical Effects Considered
- Conservation of Mass
- Conservation of Energy
- Reverse flow
- Adiabatic
- No Pressure Loss
3. Limits of Validity
- Steady flow
- Fixed control volume
- Averaging assumption violated
- The equations imply that the outlet states equal the states in the balance equations - not true for large volumes and high gradients
4. Interfaces
4.1 Physical Connectors
Basics:Interfaces:GasPortIn portA
Basics:Interfaces:GasPortOut portB
Basics:Interfaces:GasPortOut portC
5. Nomenclature
6. Governing Equations
6.1 System Description and General model approach
The model describes an ideally stirred volume element with three connection ports.
6.2 Governing Model Equations
Conservation of Mass
The dynamic mass balance is calculated as follows:
The mass inside the junction volume is calculated with the density:
Conservation of Momentum
No pressure losses are considered inside this junction:
Conservation of Energy
The energy balance considers ingoing and outgoing specific enthalpy flow rates at the ports. Please note the special structure of the energy balance with the differences of ingoing and outgoing specific enthalpies and the specific enthalpy inside the junction and the additional term for the pressure derivative which is derived from the total derivative of the inner energy of the cell. The structure results from to the special choice of state variables as discussed in Basic Concepts of Modelling.
The model's density is taken as an explicit function of the states its total derivative should be used for completeness of the model given by:
The outgoing temperatures at the ports equal the temperature inside the volume which is derived from the specific enthalpy inside the gas medium object for substance properties:
Conservation of Components
The composition is a vector of the component mass fractions. The calculation of the outlet composition depends on the type of mass conservation. If the dynamic mass balance is used, the outlet composition is calculated as follows:
The mass fractions at the ports equal the mass fractions inside the volume:
Summary
A summary record is available which bundles important component values.
7. Remarks for Usage
8. Validation
9. References
[1] Johannes Brunnemann and Friedrich Gottelt, Kai Wellner, Ala Renz, André Thüring, Volker Röder, Christoph Hasenbein, Christian Schulze, Gerhard Schmitz, Jörg Eiden: "Status of ClaRaCCS: Modelling and Simulation of Coal-Fired Power Plants with CO2 capture", 9th Modelica Conference, Munich, Germany, 2012
10. Authorship and Copyright Statement for original (initial) Contribution
Author:
DYNCAP/DYNSTART development team, Copyright 2011 - 2022.
Remarks:
This component was developed during DYNCAP/DYNSTART projects.
Acknowledgements:
ClaRa originated from the collaborative research projects DYNCAP and DYNSTART. Both research projects were supported by the German Federal Ministry for Economic Affairs and Energy (FKZ 03ET2009 and FKZ 03ET7060).
CLA:
The author(s) have agreed to ClaRa CLA, version 1.0. See https://claralib.com/pdf/CLA.pdf
By agreeing to ClaRa CLA, version 1.0 the author has granted the ClaRa development team a permanent right to use and modify his initial contribution as well as to publish it or its modified versions under the 3-clause BSD License.
11. Version History
25.06.2013 - v0.1 - initial implementation of the model - André Thüring, TLK-Thermo GmbH
Backlinks: ClaRa:Components:HeatExchangers:RegenerativeAirPreheaterSecAir L4 ClaRa:Components:HeatExchangers:RegenerativeAirPreheater L4