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Sensitivity-Based Analysis of the k-ε Model for the Turbulent Flow Between Two Plates-
Article in a journal
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Area Computational Fluid Dynamics, Optimization |
Author(s)
A. Bardow
, C. H. Bischof
, H. M. Bücker
, G. Dietze
, R. Kneer
, A. Leefken
, W. Marquardt
, U. Renz
, E. Slusanschi
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Published in
Chemical Engineering Science |
Year 2008 |
Abstract Eddy viscosity models (EVM) constitute the most successful approach for turbulence modeling in engineering applications. However, the correct formulation of EVM models is still subject to discussion, in particular the impact of model parameters on the practical relevance of models in different classes of application scenarios is not fully understood. A systematic approach for assessing parameter impact involves optimization methods for computational fluid dynamics that allow for quantitative model analysis by rigorous comparison with experimental data. In order to illustrate this systematic approach, the k-ε turbulence model is analyzed on the basis of laser Doppler velocimetry measurements for the flow between two plates. It is shown that ad-hoc approaches for adapting parameter values for the k-ε model may easily fail due to over-parameterization of the underlying model or insufficient data. Therefore, an a priori method for the identification of potential problems is important which is based on the sensitivity coefficients of the measurements with respect to the model parameters. The commercial software package FLUENT employed in our application is augmented using the automatic differentiation system ADIFOR for efficient sensitivity computation. Taken together, this results in reliable a priori methods for model assessment and calibration. Interestingly, the choice of turbulence parameters on the basis of the purely formal a priori analysis agrees quite well with physical understanding of the k-ε model. |
AD Tools ADIFOR |
BibTeX
@ARTICLE{
Bardow2008SBA,
author = "A. Bardow and C. H. Bischof and H. M. B{\"u}cker and G. Dietze and R. Kneer
and A. Leefken and W. Marquardt and U. Renz and E. Slusanschi",
title = "Sensitivity-Based Analysis of the $k$-$\varepsilon$ Model for the Turbulent Flow
Between Two Plates",
journal = "Chemical Engineering Science",
pages = "4763--4775",
doi = "10.1016/j.ces.2007.12.029",
abstract = "Eddy viscosity models (EVM) constitute the most successful approach for turbulence
modeling in engineering applications. However, the correct formulation of EVM models is still
subject to discussion, in particular the impact of model parameters on the practical relevance of
models in different classes of application scenarios is not fully understood. A systematic approach
for assessing parameter impact involves optimization methods for computational fluid dynamics that
allow for quantitative model analysis by rigorous comparison with experimental data. In order to
illustrate this systematic approach, the $k$-$\epsilon$ turbulence model is analyzed on the
basis of laser Doppler velocimetry measurements for the flow between two plates. It is shown that
ad-hoc approaches for adapting parameter values for the $k$-$\epsilon$ model may easily fail
due to over-parameterization of the underlying model or insufficient data. Therefore, an
\emph{a~priori} method for the identification of potential problems is important which is based
on the sensitivity coefficients of the measurements with respect to the model parameters. The
commercial software package FLUENT employed in our application is augmented using the automatic
differentiation system ADIFOR for efficient sensitivity computation. Taken together, this results in
reliable \emph{a~priori} methods for model assessment and calibration. Interestingly, the
choice of turbulence parameters on the basis of the purely formal a priori analysis agrees quite
well with physical understanding of the $k$-$\epsilon$ model.",
year = "2008",
volume = "63",
number = "19",
ad_area = "Computational Fluid Dynamics, Optimization",
ad_tools = "ADIFOR"
}
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