PressureLossCoefficient L2

Created Wednesday 12 June 2013

A quadratic pressure drop model - taking a pressure loss coefficient, the cross section of the device and the density of the fluid into account.

1. Purpose of Model

This model is appropriate if the user wants to define a fixed friction factor and if changes in the density of the fluid have to be expected.

2. Physical Insight

This replaceable model is compatible to models of level of detail L2 according to Brunnemann et al. [1] since the friction losses are lumped over the component. Base of this model is the quadratic pressure loss correlation for turbulent flows. Therefore, the density of the fluid and the geometry are taken into account. The calculation is done by a FluidDissipation [2] function. The model is regularized around zero, to avoid numerical instability in that point.

3. Limits of Validity

no supercritical flow conditions are supported
no phase change
only in completely developed turbulent flow with rough surfaces the friction factor is independent of the Reynolds number

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
an inCon record required for communication with FluidDissipation functions
an inVar record required for communication with FluidDissipation functions

5. Nomenclature

6. Governing Equations

The mass flow is calculated by handing over the cross sectional area , the regularization point , the pressure coefficient and the density ; ; to the FluidDissipation function "dp_pressureLossCoefficient_MFLOW" via communication records.

Eq. (1) gives the basic equation of the FluidDissipation function, see documentation for more information.

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 Simulationof Coal-Fired Power Plants with CO2 capture", 9th Modelica Conference, Munich, Germany, 2012
[2] Vahlenkamp, Thorben and Wischhusen, Stefan: "FluidDissipation for Applications - A Library for Modelling of Heat Transfer and Pressure Loss in Energy Systems", 7th Modelica Conference, Como, Italy, 2009

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