LinearPressureLoss L4
Created Friday 02 October 2015
A very robust pressure drop model - depending only of nominal values of pressure difference and mass flow rate and the actual mass flow rate
1. Purpose of Model
This model is appropriate if a pressure drop due to friction, depending on the load is needed (either due to numerical or technical reasons), but if the numerical robustness of the model is more important than accuracy. The model is parametrized by choosing a nominal load point and the corresponding pressure loss.
2. Physical Insight
This replaceable model is compatible to models of level of detail L4 according to Brunnemann et al. [1] since the friction losses are distributed according to the descretization over the component.
3. Limits of Validity
- no supercritical flow conditions are supported
- no significant changes of inlet density over time
- significant deviations from nominal point
4. Interfaces
The model communicates via outer models and records. Thus, it expects to have:
- an outer record named iCom as defined in Basics:Records:IComBase L3
- an outer model named geo as defined Fundamentals:Geometry:GenericGeometry
5. Nomenclature
6. Governing Equations
This pressure loss model bases on the LinearPressureLoss_L2 model.
The user can choose between four different flow models for this pressure loss model. This results in four cases:
(1) no pressure loss at inlet, no pressure loss at outlet
(2) no pressure loss at inlet, pressure loss at outlet
(3) pressure loss at inlet, no pressure loss at outlet
(4) pressure loss at inlet, pressure loss at outlet
See Basic Concepts of Modelling:Pressure Loss L4 Volumes for a detailed description of the idea behind the different flow models.
7. Remarks for Usage
The model can be used as long as a huge deviation for the mass flow from nominal point is not expected. For operating points which differ significantly from nominal point the accuracy can be very poor. However, the numerical robustness of the model is very good.
8. Validation
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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 Simulationof 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
- 2012 - v 0.1 - initial implementation - Friedrich Gottelt, XRG Simulation
Backlinks: ClaRa:Components:HeatExchangers:FlatTubeFinnedHEXvle2gas L4 ClaRa:Components:HeatExchangers:PlateHEXvle2vle L4 ClaRa:Components:HeatExchangers:RegenerativeAirPreheaterSecAir L4 ClaRa:Components:HeatExchangers:RegenerativeAirPreheater L4 ClaRa:Basics:ControlVolumes:FluidVolumes:VolumeVLE L4 Advanced ClaRa:Basics:ControlVolumes:GasVolumes:VolumeGas L4 ClaRa:Components:VolumesValvesFittings:Pipes:PipeFlowGas L4 Simple ClaRa:Basics:ControlVolumes:Fundamentals:PressureLoss:Generic PL:QuadraticNominalPoint L4 ClaRa:Basics:ControlVolumes:Fundamentals:PressureLoss:VLE PL:QuadraticNominalPoint L4